
AP Racing
AP Racing Radi-CAL R2 Racing Brake Fluid (500 ml)
$19.95
AP Racing Radi-CAL R2 Racing Brake Fluid
Outstanding Performance in High-Heat Braking Applications
AP Radi-CAL R2 racing brake fluid was developed for the extreme abuse of heavy race cars competing in endurance events. AP Racing Radi-CAL R2 fluid has a dry boiling point of 593º F (312º C), and was developed for racing applications where high brake temperatures are common (e.g., when using carbon discs) and very high temperature brake fluid performance is required.
Before using AP Racing Radi-CAL R2 fluid, any existing brake fluid should be drained completely from the car's brake system. The system should be thoroughly purged with new R2 and can then be filled completely with fresh R2 fluid.
AP Racing Radi-Cal R2 Brake Fluid Details:
Manufacturer: AP Racing
Manufacturer part number: AP-CP5600
R2 fluid conforms to and exceeds DOT4 specifications, but should not be used with components made from magnesium
Dry Boiling Point: 593º F / 312º C
Wet Boiling Point: 383º F / 195º C
Bottle Size: 500 ml (16.9 fl. oz.)

AP Racing
AP Racing Radi-CAL R4 Racing Brake Fluid (500 ml)
$39.25
AP Racing Radi-CAL R4 Racing Brake Fluid
Among the Highest Dry Boilings Point On The Market Today
AP Racing Radi-CAL R4 racing brake fluid has an ultra-high typical dry boiling point, at 644º F / 340º C. Radi-CAL R4 racing brake fluid has been designed to perform better than any other product at the extremes of heavy-duty braking in top levels of professional racing.
AP Racing Radi-CAL R4 has outstanding resistance to vapor lock and pedal fade under the most exacting conditions. A higher vapor lock point means a firmer brake pedal at the extremes of brake temperatures. Enhanced lubricity means R4 is a better lubricant than other market-leading racing brake fluids. This helps extend the life of the metal moving parts in your brake system while increasing system efficiency.
Radi-CAL R4 can be mixed with other DOT 3 and DOT 4 racing brake fluid, although for maximum performance your braking system should be thoroughly purged with R4 fluid.
AP Racing Radi-Cal Pro R4 Brake Fluid Details:
Manufacturer: AP Racing
Manufacturer part number: AP-CP7005
DOT rating: DOT 4
Dry Boiling Point: 644º F / 340º C
Wet Boiling Point: 383º F / 195º C
Bottle Size: 500 ml (16.9 fl. oz.)

AP Racing
AP Racing Radi-CAL R1 Racing Brake Fluid (500 ml)
$17.95
AP Racing Radi-CAL R1 Racing Brake Fluid
Brake Fluid Suitable for All Forms of Motorsport
AP Racing Radi-CAL R1 DOT 4 racing brake fluid was developed for road cars being used in events such as autocross and track days, where drivers need brake fluid with a higher boiling point than that of standard OEM brake fluid.
While AP Racing Radi-CAL R1 fluid has the lowest dry boiling point of AP Racing's racing brake fluid lineup at 516º F (269º C), it far exceeds that of ordinary DOT 4 brake fluid. It was developed for applications needing more heat resistance than typical OEM brake fluid.
AP Racing Radi-CAL R1 Brake Fluid Details:
Manufacturer: AP Racing
Conforms to FMVSS 116 DOT3 specification
Manufacturer part number: AP-CP7551
New Dry Boiling Point: 516º F / 269º C
Wet Boiling Point: 284º F / 140º C
Bottle Size: 500 ml (16.9 fl. oz.)

AP Racing
AP Racing 408x34mm 2-piece J Hook Front Brake Rotors - Porsche GT4RS (OEM Iron & PCCB)
$2,499.00
AP Racing by Essex 2-piece "S" Vane J Hook Front Brake Rotors (Front 408 x 34mm)- Porsche GT4RS Iron & PCCB
Fit The Following Cars (w/ OEM Iron Rotors or PCCB Rotors)
Porsche GT4RS OEM Iron or PCCB (Front)
Sold/priced per pair.
AP Racing 2-piece S Vane Competition J Hook front disc pair for GT4RS with iron or PCCB discs.
***Note for PCCB cars - must be used with the smaller D62 iron disc pad shape (Ferodo FCP4664 - DS3.12 / DS1.11)
Massive increase in airflow, cooling capacity, and durability vs. OEM discs or even conventional curved vane discs
408mm x 34mm (16.06" x 1.34") , 84 Sinusoidal "wave" vanes, D62 radial depth
Designed for: club racing, time trial, autocross, HPDE
Works with OEM calipers, no modifications required
Ultralight, fully floating, anodized billet aluminum hat with float control/anti-rattle clips
We are introducing a new internal vane technology in our front 2-piece discs for the GT4RS. It is called the Sinusoidal Vane, which AP sometimes refers to internally as the 'Wave' Vane for obvious reasons as you’ll see below. This tech is something that has helped AP Racing brake systems win championships in international GT racing, as well as multiple NASCAR Cup championships here in North America. As one of the most desirable track weapons on the planet, we wanted the GT4RS to be the first production car application for this technology in North America. Just as AP Racing's Radi-CAL calipers set a new benchmark for caliper stability, cooling, and durability, the Sinusoidal Vanes have done the same for iron racing discs.
The concept for this disc design originated in NASCAR Cup. Up until the debut of the Next Gen car (for which AP/Essex are supplying the spec brake package), we were cramming our brake systems inside tiny 15” wheels. Trying to squeeze adequate brake thermal mass into a wheel that small is incredibly challenging, particularly when you have a 1,000 HP and 3,000 pounds mashing on them every few seconds from 200 mph…for hours on end! In a wheel that small, there isn’t anywhere for the heat to go, and the durability of every component is crucial. We were constantly looking for ways to provide the Cup teams with increased durability, stability, and cooling, and that’s what led AP to this technology.
Benefits of the Wave Vane disc technology vs. traditional curved vanes:
Increased thermal stability- Wild temperature swings are what causes discs to crack. When you stand on the brakes for an approaching corner, your disc temperatures skyrocket and the iron expands. As you travel down the subsequent straight, the discs are blasted with cooling air. The longer the straight and the higher the speed, the greater the temperature drop, and the further the iron contracts. This expansion and contraction cycle places a huge amount of stress on the iron and is what causes them to eventually crack. That’s why tracks with relatively slow corners at the end of high-speed straights, followed by another long straight, decimate brake discs (think Watkins Glen or Road America). In an ideal world, once you brought your discs up to race temps, you would keep them at a constant temperature for the entire session. The Sinusoidal Vane brings the discs closer to that goal by decreasing the difference between the maximum and minimum disc temperature by as much as 35%. That means a less dramatic temperature swing and greater crack resistance and durability.
Reduced maximum disc temperatures by 10%+: Not only are temperature swings less intense with the Wave Vane, the maximum temperatures reached are substantially lower. For example, in one NASCAR test the Wave Vane discs showed a peak temp of 1328F and a minimum temp of 1085F (delta of 243F), while the traditional curved vanes maxed out at 1490F and a min of 1121F (delta of 369F). Not only was the difference between min and max more subdued, the max temperature reached by the Wave Vane disc was 162F lower!
Increased cooling surface area- Each of the internal Wave Vanes has a larger cooling surface area vs. a traditional curved vane.
Greater support for the disc face- A disc’s internal vane structure provides the support lattice behind the disc face. Having many internal vanes impacts airspeed and heat transfer through the disc, reduces air recirculation between vanes, and reduces deflection at the disc face. In practical terms, a disc with a high number of vanes is more thermally stable, maintains more even contact with the brake pads (which reduces uneven pad deposits/judder), and is less prone to distortion. In summary, the Wave Vane design provides even greater support for the disc face than AP’s standard curved vane designs.
Reduced weight- The Wave Vane design provides a slight unsprung weight reduction vs. a similar disc with curved internal vanes.
AP Racing J Hook Brake Rotors – The Gold Standard in Track Day & Racing Performance
Engineered for professional motorsport, HPDE, and dedicated track day use, AP Racing’s J Hook Brake Rotors deliver uncompromising performance, thermal stability, and consistent braking power. These two-piece, floating rotors are built to handle the extreme demands of road racing, with design features derived from over 50 years of elite competition—including Formula 1, NASCAR, and IMSA.
Unlike conventional one-piece rotors, AP Racing’s two-piece floating design features a billet aluminum hat mated to a cast iron disc via precision-engineered bobbins. This setup allows for controlled radial expansion under high heat, minimizing distortion and coning. The result? More even pad wear, a firmer pedal feel, and longer component life, even during extended lapping sessions or endurance racing. Floating hardware includes anti-knockback spring clips that reduce piston retraction while eliminating common NVH issues like rattling.
Why Choose AP Racing J Hook Rotors? Advanced Cooling, Superior Bite, Unmatched Durability
At the heart of every rotor is AP Racing’s proprietary high-carbon iron alloy, developed to withstand repeated thermal cycling without cracking or warping. Internally, directional vanes—far superior to OEM pillar or straight vane designs—maximize airflow and cooling. With 60 to 84 vanes per rotor, AP Racing achieves faster heat evacuation, reduced brake fade, and a more consistent friction surface. These rotors are left/right-specific for optimal airflow and balance.
The exclusive J Hook slot pattern offers enhanced initial bite and promotes uniform heat distribution across the rotor face, reducing pad deposits and vibration. Unlike drilled rotors or straight-slot competitors, the J Hook design provides cleaner pad transfer during bed-in and superior modulation under braking—ideal for serious drivers who demand feedback and control. Yes, you might hear a little more whirr, but you’ll gain the stopping power, consistency, and longevity your lap times demand.
Premium Components, Affordable Performance
The rotor hats are CNC-machined from 6061-T6 billet aluminum and hard anodized for strength and heat resistance. Scalloped edges under the hat further assist heat dissipation. All hardware is U.S.-made to AP Racing spec, the same quality found on pro-level racing platforms.
And while these rotors are race-proven, they’re also surprisingly cost-effective to replace. Don’t settle for cheap rotors that crack after a weekend—AP’s J Hook rings offer better durability and real long-term value. Fewer replacements mean more track time, less downtime, and peace of mind knowing you're running the best.
Used by Champions. Trusted by Experts.
From endurance racers to HPDE enthusiasts, AP Racing brake rotors are trusted worldwide for their reliability, longevity, and performance under pressure. Whether you're shaving seconds off your lap time or building a dedicated track car, the J Hook delivers a professional-grade solution that won’t let you down.
AP Racing J Hook Brake Rotors for Auto Racing, Track Days & HPDE
Why Rotor Design Matters: Heat Expansion and Floating Technology
As with most metals, iron brake discs expand significantly under heat. When temperatures rise, the disc grows radially—expanding in both diameter and circumference. Traditional one-piece rotors struggle to accommodate this natural expansion. As the outer edge pulls away from the center under heat stress, it creates a condition called “coning”—a distortion that compromises pad-to-rotor contact. This distortion can lead to uneven pad wear, brake tapering, and an inconsistent, long brake pedal.
AP Racing two-piece floating brake rotors are purpose-built to eliminate these issues. Engineered with “float” built into the disc or hat assembly, these rotors feature oblong-shaped mounting holes that allow the hardware to slide as the disc heats up. This flexibility ensures the disc runs true within the caliper under high-temperature loads, effectively reducing distortion, minimizing pad taper and stress cracks, and promoting longer component life.
Custom Mounting Hardware & Anti-Knockback Spring Clips
AP Racing rotors utilize application-specific, U.S.-made mounting hardware—not generic bolts. These premium components are the exact parts used in AP’s professional motorsport products, engineered to withstand the rigors of competitive racing.
To manage lateral disc motion that can push caliper pistons backward (known as knockback), AP Racing integrates anti-knockback spring clips on alternating bobbins—five on a ten-bolt setup, six on a twelve-bolt disc. These clips keep the aluminum hat and iron disc ring properly aligned while still allowing for radial float. Bonus: they eliminate annoying rattles and vibrations, ensuring a quieter, more refined braking experience.
High-Performance Hat Design for Heat Isolation
The disc hats in AP Racing’s two-piece floating rotors are CNC-machined from 6061-T6 billet aluminum and finished with a hard anodized coating. This high-strength aluminum alloy was selected for its ability to maintain structural integrity even at elevated temperatures. AP adds scalloped channels beneath the hat to further encourage airflow and heat evacuation from the outer disc face, minimizing thermal transfer to hubs and wheel bearings—helping reduce maintenance costs on these expensive components.
J Hook Slot Pattern: Exclusive to AP Racing
Slots and drill holes may improve initial bite, but they also introduce “cool spots” in the rotor face—areas of uneven heating that can lead to stress risers, cracks, and pad vibration. OEM rotors often avoid this by leaving the disc face blank, but that compromises bite and brake feel.
AP Racing’s patented J Hook design, developed through rigorous R&D, solves this problem. The hooks are meticulously spaced around the disc’s circumference and from hat to edge, forming a continuous distortion path that ensures even heat distribution. This encourages uniform pad deposits during bed-in, helps reduce judder and cracking, and improves consistency under repeated high-load braking.
In addition, the J Hook slots provide more leading edges for pads to grip than traditional curved slots or blank rotors. While this might generate a mild whirring sound during braking, the benefits—more bite, cleaner bedding, better pedal feel—make it the top choice for committed racers and serious track day drivers.
Metallurgy Backed by 50+ Years of Motorsport Leadership
AP Racing's reputation is built on performance, and their proprietary iron alloy used in J Hook rotors is no exception. Drawing from over five decades of elite motorsport experience, including 750+ Formula 1 wins and widespread use across NASCAR, AP’s engineers have developed a disc alloy that excels under sustained racing temperatures and stress. Where OEM discs focus on affordability and mass production, AP Racing’s J Hook rotors are purpose-built for motorsport durability and heat resistance.
Affordable Replacement Cost: Serious Value for Serious Drivers
Even the best brake rotors are consumables. When you drive hard—especially at the track—your discs will eventually wear out. That’s why AP Racing designed their replacement iron rings to be cost-effective, allowing you to replace worn parts without breaking the bank.
Compare that to constantly buying cheap $150 rotors every weekend—rotors that can't handle the heat and need to be swapped frequently. With AP Racing’s J Hook rotors, you get longer service intervals, less downtime, and better performance over time, making them an incredibly smart long-term investment.
Proven on Track. Trusted by Champions.
Top-tier racing teams rely on AP Racing J Hook rotors for one reason: they perform under pressure. Whether you're running time trials, attending HPDE events, or competing in wheel-to-wheel racing, these rotors offer professional-grade reliability, safety, and performance.
Bedding and preparation of AP Racing J Hook Disc
Properly preparing your new brake discs before heavy use is extremely important. The goal of bedding-in your brake pads and discs is to mate them together properly and prepare them for heavy use. When prepared properly, or bed-in, your pads will transfer a thin layer of material to the disc face (transfer layer). The pads in your caliper will then actually ride on that thin layer of pad material you’ve put down on the rotor, rather than rubbing directly on the iron rotor face. A good transfer layer is going to give you superior brake pedal feel, less noise, superior pad wear, and lower the chances of cracking your discs.
Important Notes- PLEASE READ! First, make sure you are on a closed course to perform a proper bed-in. Do NOT perform the procedure on public roads. You need a stretch of asphalt with long straights, good visibility, and no potential obstructions. Make sure you are in a position to safely and repeatedly attain the necessary speeds to perform the bed-in procedure. A controlled racetrack is the best place to perform this procedure. AP Racing and Competition Motorsport in no way suggest or condone speeding on public roads or breaking the law in your car, nor do we take responsibility for any damage or injury that occurs as a result of using our product or these procedures. You are performing the bed-in procedure at your own risk.
During these procedures, it’s critical that you never come to a complete stop with your foot on the brake pedal. If you have brake ducts on your car, you may want to block them off to allow your brake system to heat up easily. The procedure outlined below is a generic procedure for most types of mild race pad. Please check your pad manufacturer’s recommended bed-in procedure.
Accelerate to approximately 60mph and then decelerate down to 5 mph. If your car has ABS, you should try to hold the brakes at a point just before ABS intervention.
Once the car slows to 5mph, immediately accelerate back up to about 60mph, and brake again to roughly 5mph.
Repeat this series of stopping and accelerating 8 to 10 times. Again, do not come to a complete stop with your foot on the brake pedal.
Cool the brake system down by cruising at 45mph+ for 5 to 10 minutes.
Visually inspect your discs. They should be a blue/grey color (instead of shiny silver), and have an even layer of pad material across and around the entire rotor face.
If the AP Racing rotors don’t have a layer of pad material on them, perform another series of stops in the manner outlined above.

AP Racing
AP Racing 410x36mm Replacement Front Brake Rotor Rings for Porsche (OEM PCCB)
$1,596.00
AP Racing J Hook 410x36mm Replacement Front Brake Rotor Rings
This is a pair of replacement front rotor rings with new hardware included. Center hat is not included, this kit is rotor rings and hardware only. Replacement discs only for AP Racing 13.01.20025 rotors.
Fits the Following Cars (w/ OEM PCCB rotors):
Porsche 991 GT2RS PCCB (Front)
Porsche 991 GT3 PCCB (Front)
Porsche 991 GT3RS PCCB (Front)
Porsche 718 GT4 PCCB (Front)
Sold/priced per pair of rotor rings with hardware.
AP Racing J Hook Brake Rotors – The Gold Standard in Track Day & Racing Performance
Engineered for professional motorsport, HPDE, and dedicated track day use, AP Racing’s J Hook Brake Rotors deliver uncompromising performance, thermal stability, and consistent braking power. These two-piece, floating rotors are built to handle the extreme demands of road racing, with design features derived from over 50 years of elite competition—including Formula 1, NASCAR, and IMSA.
Unlike conventional one-piece rotors, AP Racing’s two-piece floating design features a billet aluminum hat mated to a cast iron disc via precision-engineered bobbins. This setup allows for controlled radial expansion under high heat, minimizing distortion and coning. The result? More even pad wear, a firmer pedal feel, and longer component life, even during extended lapping sessions or endurance racing. Floating hardware includes anti-knock back spring clips that reduce piston retraction while eliminating common NVH issues like rattling.
Why Choose AP Racing J Hook Rotors? Advanced Cooling, Superior Bite, Unmatched Durability
At the heart of every rotor is AP Racing’s proprietary high-carbon iron alloy, developed to withstand repeated thermal cycling without cracking or warping. Internally, directional vanes—far superior to OEM pillar or straight vane designs—maximize airflow and cooling. With 60 to 84 vanes per rotor, AP Racing achieves faster heat evacuation, reduced brake fade, and a more consistent friction surface. These rotors are left/right-specific for optimal airflow and balance.
The exclusive J Hook slot pattern offers enhanced initial bite and promotes uniform heat distribution across the rotor face, reducing pad deposits and vibration. Unlike drilled rotors or straight-slot competitors, the J Hook design provides cleaner pad transfer during bed-in and superior modulation under braking—ideal for serious drivers who demand feedback and control. Yes, you might hear a little more whirr, but you’ll gain the stopping power, consistency, and longevity your lap times demand.
Premium Components, Affordable Performance
The rotor hats are CNC-machined from 6061-T6 billet aluminum and hard anodized for strength and heat resistance. Scalloped edges under the hat further assist heat dissipation. All hardware is U.S.-made to AP Racing spec, the same quality found on pro-level racing platforms.
And while these rotors are race-proven, they’re also surprisingly cost-effective to replace. Don’t settle for cheap rotors that crack after a weekend—AP’s J Hook rings offer better durability and real long-term value. Fewer replacements mean more track time, less downtime, and peace of mind knowing you're running the best.
Used by Champions. Trusted by Experts.
From endurance racers to HPDE enthusiasts, AP Racing brake rotors are trusted worldwide for their reliability, longevity, and performance under pressure. Whether you're shaving seconds off your lap time or building a dedicated track car, the J Hook delivers a professional-grade solution that won’t let you down.
AP Racing by Essex 2-piece Competition J Hook front iron disc pair for 991 GT3/RS and 718 GT4/Spyder RS to replace PCCB discs.
410x36mm (16.14" x 1.40")
Huge increase in airflow, cooling capacity, and durability vs. OEM PCCB discs
Drastically less expense long-term running costs vs. PCCB
Must use the standard front 991 GT3/RS pad shape used in the OEM iron rotors system
Not compatible with OEM PCCB pad shape
Over twice as many internal cooling vanes as the OEM PCCB's
Weighs almost the same as the OEM 380x34mm iron discs, despite much larger size
Designed for: club racing, time trial, auto-x, HPDE
Works with OEM calipers and wheels, no modifications required
Ultralight, fully floating, anodized billet aluminum hat with float control/anti-rattle clips
AP Racing J Hook Brake Rotors for Auto Racing, Track Days & HPDE
Why Rotor Design Matters: Heat Expansion and Floating Technology
As with most metals, iron brake discs expand significantly under heat. When temperatures rise, the disc grows radially—expanding in both diameter and circumference. Traditional one-piece rotors struggle to accommodate this natural expansion. As the outer edge pulls away from the center under heat stress, it creates a condition called “coning”—a distortion that compromises pad-to-rotor contact. This distortion can lead to uneven pad wear, brake tapering, and an inconsistent, long brake pedal.
AP Racing two-piece floating brake rotors are purpose-built to eliminate these issues. Engineered with “float” built into the disc or hat assembly, these rotors feature oblong-shaped mounting holes that allow the hardware to slide as the disc heats up. This flexibility ensures the disc runs true within the caliper under high-temperature loads, effectively reducing distortion, minimizing pad taper and stress cracks, and promoting longer component life.
Custom Mounting Hardware & Anti-Knock Back Spring Clips
AP Racing rotors utilize application-specific, U.S.-made mounting hardware—not generic bolts. These premium components are the exact parts used in AP’s professional motorsport products, engineered to withstand the rigors of competitive racing.
To manage lateral disc motion that can push caliper pistons backward (known as knock back), AP Racing integrates anti-knock back spring clips on alternating bobbins—five on a ten-bolt setup, six on a twelve-bolt disc. These clips keep the aluminum hat and iron disc ring properly aligned while still allowing for radial float. Bonus: they eliminate annoying rattles and vibrations, ensuring a quieter, more refined braking experience.
High-Performance Hat Design for Heat Isolation
The disc hats in AP Racing’s two-piece floating rotors are CNC-machined from 6061-T6 billet aluminum and finished with a hard anodized coating. This high-strength aluminum alloy was selected for its ability to maintain structural integrity even at elevated temperatures. AP adds scalloped channels beneath the hat to further encourage airflow and heat evacuation from the outer disc face, minimizing thermal transfer to hubs and wheel bearings—helping reduce maintenance costs on these expensive components.
Internal Vane Engineering: Airflow Optimization & Thermal Stability
AP Racing’s internal vane design sets them apart from OEM and most aftermarket competitors. While many factory brake discs use non-directional pillar vanes (low-cost and NVH-focused), AP Racing rotors use directional vanes engineered for maximum airflow. These rotors are side-specific—meaning you’ll receive a unique left and right disc in each set—ensuring optimized cooling through strategic vane orientation and shape.
Beyond that, AP Racing rotors feature a superior vane count, typically ranging from 60 to 84 vanes, compared to 30–48 in most aftermarket rotors. After extensive CFD and thermal analysis, this high vane count was proven to:
Increase airspeed and thermal transfer
Reduce recirculation and deflection at the disc face
Minimize coning, cracking, and brake fade
Deliver more even pad contact and extended rotor life
J Hook Slot Pattern: Exclusive to AP Racing
Slots and drill holes may improve initial bite, but they also introduce “cool spots” in the rotor face—areas of uneven heating that can lead to stress risers, cracks, and pad vibration. OEM rotors often avoid this by leaving the disc face blank, but that compromises bite and brake feel.
AP Racing’s patented J Hook design, developed through rigorous R&D, solves this problem. The hooks are meticulously spaced around the disc’s circumference and from hat to edge, forming a continuous distortion path that ensures even heat distribution. This encourages uniform pad deposits during bed-in, helps reduce judder and cracking, and improves consistency under repeated high-load braking.
In addition, the J Hook slots provide more leading edges for pads to grip than traditional curved slots or blank rotors. While this might generate a mild whirring sound during braking, the benefits—more bite, cleaner bedding, better pedal feel—make it the top choice for committed racers and serious track day drivers.
Metallurgy Backed by 50+ Years of Motorsport Leadership
AP Racing's reputation is built on performance, and their proprietary iron alloy used in J Hook rotors is no exception. Drawing from over five decades of elite motorsport experience, including 750+ Formula 1 wins and widespread use across NASCAR, AP’s engineers have developed a disc alloy that excels under sustained racing temperatures and stress. Where OEM discs focus on affordability and mass production, AP Racing’s J Hook rotors are purpose-built for motorsport durability and heat resistance.
Affordable Replacement Cost: Serious Value for Serious Drivers
Even the best brake rotors are consumables. When you drive hard—especially at the track—your discs will eventually wear out. That’s why AP Racing designed their replacement iron rings to be cost-effective, allowing you to replace worn parts without breaking the bank.
Compare that to constantly buying cheap $150 rotors every weekend—rotors that can't handle the heat and need to be swapped frequently. With AP Racing’s J Hook rotors, you get longer service intervals, less downtime, and better performance over time, making them an incredibly smart long-term investment.
Proven on Track. Trusted by Champions.
Top-tier racing teams rely on AP Racing J Hook rotors for one reason: they perform under pressure. Whether you're running time trials, attending HPDE events, or competing in wheel-to-wheel racing, these rotors offer professional-grade reliability, safety, and performance.
Bedding and Preparation of AP Racing J Hook Discs
Properly preparing your new brake discs before heavy use is extremely important. The goal of bedding-in your brake pads and discs is to mate them together properly and prepare them for heavy use. When prepared properly, or bed-in, your pads will transfer a thin layer of material to the disc face (transfer layer). The pads in your caliper will then actually ride on that thin layer of pad material you’ve put down on the rotor, rather than rubbing directly on the iron rotor face. A good transfer layer is going to give you superior brake pedal feel, less noise, superior pad wear, and lower the chances of cracking your discs.
Important Notes- PLEASE READ! First, make sure you are on a closed course to perform a proper bed-in. Do NOT perform the procedure on public roads. You need a stretch of asphalt with long straights, good visibility, and no potential obstructions. Make sure you are in a position to safely and repeatedly attain the necessary speeds to perform the bed-in procedure. A controlled racetrack is the best place to perform this procedure. AP Racing and Competition Motorsport in no way suggest or condone speeding on public roads or breaking the law in your car, nor do we take responsibility for any damage or injury that occurs as a result of using our product or these procedures. You are performing the bed-in procedure at your own risk.
During these procedures, it’s critical that you never come to a complete stop with your foot on the brake pedal. If you have brake ducts on your car, you may want to block them off to allow your brake system to heat up easily. The procedure outlined below is a generic procedure for most types of mild race pad. Please check your pad manufacturer’s recommended bed-in procedure.
Accelerate to approximately 60mph and then decelerate down to 5 mph. If your car has ABS, you should try to hold the brakes at a point just before ABS intervention.
Once the car slows to 5mph, immediately accelerate back up to about 60mph, and brake again to roughly 5mph.
Repeat this series of stopping and accelerating 8 to 10 times. Again, do not come to a complete stop with your foot on the brake pedal.
Cool the brake system down by cruising at 45mph+ for 5 to 10 minutes.
Visually inspect your discs. They should be a blue/grey color (instead of shiny silver), and have an even layer of pad material across and around the entire rotor face.
If the AP Racing rotors don’t have a layer of pad material on them, perform another series of stops in the manner outlined above.

AP Racing
AP Racing 410x36mm 2-piece J Hook Front Brake Rotors - Porsche (OEM PCCB)
$2,599.00
AP Racing 410x36mm Two-Piece Front Floating Racing Brake Rotors
Fit The Following Cars (w/ OEM PCCB Rotors)
Porsche 991 GT2RS PCCB (Front)
Porsche 991 GT3 PCCB (Front)
Porsche 991 GT3RS PCCB (Front)
Porsche 718 GT4 PCCB (Front)
Sold/priced per pair.
AP Racing by Essex 2-piece Competition J Hook front iron disc pair for 991 GT3/RS and 718 GT4/Spyder RS to replace PCCB discs.
410x36mm (16.14" x 1.40")
Huge increase in airflow, cooling capacity, and durability vs. OEM PCCB discs
Drastically less expense long-term running costs vs. PCCB
Must use the standard front 991 GT3/RS pad shape used in OEM iron system (not compatible with OE PCCB pad shape)
Over twice as many internal cooling vanes as the OEM PCCB's
Weighs almost the same as the OEM 380x34mm iron discs, despite much larger size
Designed for: club racing, time trial, auto-x, HPDE
Works with OEM calipers and wheels, no modifications required
Ultralight, fully floating, anodized billet aluminum hat with float control/anti-rattle clips
AP Racing J Hook Brake Rotors – The Gold Standard in Track Day & Racing Performance
Engineered for professional motorsport, HPDE, and dedicated track day use, AP Racing’s J Hook Brake Rotors deliver uncompromising performance, thermal stability, and consistent braking power. These two-piece, floating rotors are built to handle the extreme demands of road racing, with design features derived from over 50 years of elite competition—including Formula 1, NASCAR, and IMSA.
Unlike conventional one-piece rotors, AP Racing’s two-piece floating design features a billet aluminum hat mated to a cast iron disc via precision-engineered bobbins. This setup allows for controlled radial expansion under high heat, minimizing distortion and coning. The result? More even pad wear, a firmer pedal feel, and longer component life, even during extended lapping sessions or endurance racing. Floating hardware includes anti-knockback spring clips that reduce piston retraction while eliminating common NVH issues like rattling.
Why Choose AP Racing J Hook Rotors? Advanced Cooling, Superior Bite, Unmatched Durability
At the heart of every rotor is AP Racing’s proprietary high-carbon iron alloy, developed to withstand repeated thermal cycling without cracking or warping. Internally, directional vanes—far superior to OEM pillar or straight vane designs—maximize airflow and cooling. With 60 to 84 vanes per rotor, AP Racing achieves faster heat evacuation, reduced brake fade, and a more consistent friction surface. These rotors are left/right-specific for optimal airflow and balance.
The exclusive J Hook slot pattern offers enhanced initial bite and promotes uniform heat distribution across the rotor face, reducing pad deposits and vibration. Unlike drilled rotors or straight-slot competitors, the J Hook design provides cleaner pad transfer during bed-in and superior modulation under braking—ideal for serious drivers who demand feedback and control. Yes, you might hear a little more whirr, but you’ll gain the stopping power, consistency, and longevity your lap times demand.
Premium Components, Affordable Performance
The rotor hats are CNC-machined from 6061-T6 billet aluminum and hard anodized for strength and heat resistance. Scalloped edges under the hat further assist heat dissipation. All hardware is U.S.-made to AP Racing spec, the same quality found on pro-level racing platforms.
And while these rotors are race-proven, they’re also surprisingly cost-effective to replace. Don’t settle for cheap rotors that crack after a weekend—AP’s J Hook rings offer better durability and real long-term value. Fewer replacements mean more track time, less downtime, and peace of mind knowing you're running the best.
Used by Champions. Trusted by Experts.
From endurance racers to HPDE enthusiasts, AP Racing brake rotors are trusted worldwide for their reliability, longevity, and performance under pressure. Whether you're shaving seconds off your lap time or building a dedicated track car, the J Hook delivers a professional-grade solution that won’t let you down.
AP Racing J Hook Brake Rotors for Auto Racing, Track Days & HPDE
Why Rotor Design Matters: Heat Expansion and Floating Technology
As with most metals, iron brake discs expand significantly under heat. When temperatures rise, the disc grows radially—expanding in both diameter and circumference. Traditional one-piece rotors struggle to accommodate this natural expansion. As the outer edge pulls away from the center under heat stress, it creates a condition called “coning”—a distortion that compromises pad-to-rotor contact. This distortion can lead to uneven pad wear, brake tapering, and an inconsistent, long brake pedal.
AP Racing two-piece floating brake rotors are purpose-built to eliminate these issues. Engineered with “float” built into the disc or hat assembly, these rotors feature oblong-shaped mounting holes that allow the hardware to slide as the disc heats up. This flexibility ensures the disc runs true within the caliper under high-temperature loads, effectively reducing distortion, minimizing pad taper and stress cracks, and promoting longer component life.
Custom Mounting Hardware & Anti-Knockback Spring Clips
AP Racing rotors utilize application-specific, U.S.-made mounting hardware—not generic bolts. These premium components are the exact parts used in AP’s professional motorsport products, engineered to withstand the rigors of competitive racing.
To manage lateral disc motion that can push caliper pistons backward (known as knockback), AP Racing integrates anti-knockback spring clips on alternating bobbins—five on a ten-bolt setup, six on a twelve-bolt disc. These clips keep the aluminum hat and iron disc ring properly aligned while still allowing for radial float. Bonus: they eliminate annoying rattles and vibrations, ensuring a quieter, more refined braking experience.
High-Performance Hat Design for Heat Isolation
The disc hats in AP Racing’s two-piece floating rotors are CNC-machined from 6061-T6 billet aluminum and finished with a hard anodized coating. This high-strength aluminum alloy was selected for its ability to maintain structural integrity even at elevated temperatures. AP adds scalloped channels beneath the hat to further encourage airflow and heat evacuation from the outer disc face, minimizing thermal transfer to hubs and wheel bearings—helping reduce maintenance costs on these expensive components.
Internal Vane Engineering: Airflow Optimization & Thermal Stability
AP Racing’s internal vane design sets them apart from OEM and most aftermarket competitors. While many factory brake discs use non-directional pillar vanes (low-cost and NVH-focused), AP Racing rotors use directional vanes engineered for maximum airflow. These rotors are side-specific—meaning you’ll receive a unique left and right disc in each set—ensuring optimized cooling through strategic vane orientation and shape.
Beyond that, AP Racing rotors feature a superior vane count, typically ranging from 60 to 84 vanes, compared to 30–48 in most aftermarket rotors. After extensive CFD and thermal analysis, this high vane count was proven to:
Increase airspeed and thermal transfer
Reduce recirculation and deflection at the disc face
Minimize coning, cracking, and brake fade
Deliver more even pad contact and extended rotor life
J Hook Slot Pattern: Exclusive to AP Racing
Slots and drill holes may improve initial bite, but they also introduce “cool spots” in the rotor face—areas of uneven heating that can lead to stress risers, cracks, and pad vibration. OEM rotors often avoid this by leaving the disc face blank, but that compromises bite and brake feel.
AP Racing’s patented J Hook design, developed through rigorous R&D, solves this problem. The hooks are meticulously spaced around the disc’s circumference and from hat to edge, forming a continuous distortion path that ensures even heat distribution. This encourages uniform pad deposits during bed-in, helps reduce judder and cracking, and improves consistency under repeated high-load braking.
In addition, the J Hook slots provide more leading edges for pads to grip than traditional curved slots or blank rotors. While this might generate a mild whirring sound during braking, the benefits—more bite, cleaner bedding, better pedal feel—make it the top choice for committed racers and serious track day drivers.
Metallurgy Backed by 50+ Years of Motorsport Leadership
AP Racing's reputation is built on performance, and their proprietary iron alloy used in J Hook rotors is no exception. Drawing from over five decades of elite motorsport experience, including 750+ Formula 1 wins and widespread use across NASCAR, AP’s engineers have developed a disc alloy that excels under sustained racing temperatures and stress. Where OEM discs focus on affordability and mass production, AP Racing’s J Hook rotors are purpose-built for motorsport durability and heat resistance.
Affordable Replacement Cost: Serious Value for Serious Drivers
Even the best brake rotors are consumables. When you drive hard—especially at the track—your discs will eventually wear out. That’s why AP Racing designed their replacement iron rings to be cost-effective, allowing you to replace worn parts without breaking the bank.
Compare that to constantly buying cheap $150 rotors every weekend—rotors that can't handle the heat and need to be swapped frequently. With AP Racing’s J Hook rotors, you get longer service intervals, less downtime, and better performance over time, making them an incredibly smart long-term investment.
Proven on Track. Trusted by Champions.
Top-tier racing teams rely on AP Racing J Hook rotors for one reason: they perform under pressure. Whether you're running time trials, attending HPDE events, or competing in wheel-to-wheel racing, these rotors offer professional-grade reliability, safety, and performance.
Bedding and preparation of AP Racing J Hook Disc
Properly preparing your new brake discs before heavy use is extremely important. The goal of bedding-in your brake pads and discs is to mate them together properly and prepare them for heavy use. When prepared properly, or bed-in, your pads will transfer a thin layer of material to the disc face (transfer layer). The pads in your caliper will then actually ride on that thin layer of pad material you’ve put down on the rotor, rather than rubbing directly on the iron rotor face. A good transfer layer is going to give you superior brake pedal feel, less noise, superior pad wear, and lower the chances of cracking your discs.
Important Notes- PLEASE READ! First, make sure you are on a closed course to perform a proper bed-in. Do NOT perform the procedure on public roads. You need a stretch of asphalt with long straights, good visibility, and no potential obstructions. Make sure you are in a position to safely and repeatedly attain the necessary speeds to perform the bed-in procedure. A controlled racetrack is the best place to perform this procedure. AP Racing and Competition Motorsport in no way suggest or condone speeding on public roads or breaking the law in your car, nor do we take responsibility for any damage or injury that occurs as a result of using our product or these procedures. You are performing the bed-in procedure at your own risk.
During these procedures, it’s critical that you never come to a complete stop with your foot on the brake pedal. If you have brake ducts on your car, you may want to block them off to allow your brake system to heat up easily. The procedure outlined below is a generic procedure for most types of mild race pad. Please check your pad manufacturer’s recommended bed-in procedure.
Accelerate to approximately 60mph and then decelerate down to 5 mph. If your car has ABS, you should try to hold the brakes at a point just before ABS intervention.
Once the car slows to 5mph, immediately accelerate back up to about 60mph, and brake again to roughly 5mph.
Repeat this series of stopping and accelerating 8 to 10 times. Again, do not come to a complete stop with your foot on the brake pedal.
Cool the brake system down by cruising at 45mph+ for 5 to 10 minutes.
Visually inspect your discs. They should be a blue/grey color (instead of shiny silver), and have an even layer of pad material across and around the entire rotor face.
If the AP Racing rotors don’t have a layer of pad material on them, perform another series of stops in the manner outlined above.

AP Racing
AP Racing 390x32mm Replacement Rear Brake Rotor Rings for Porsche (OEM PCCB)
$1,596.00
AP Racing J Hook 390x32mm Replacement Front Brake Rotor Rings
This kit is two replacement rotor discs and associated installation hardware only. Center hat is not included. Replacement discs for AP Racing 13.01.20026.
Fits The Following Cars (w/ OEM PCCB rotors):
Porsche 992 GT3 (Rear)
Porsche 992 GT3RS (Rear)
Porsche 718/982 GT4RS (Rear)
Porsche 991 GT2RS/GT3/GT3RS (Rear)
Porsche 981 GT4 (Rear)
Sold/priced per pair of rotor rings (including hardware).
390x32mm (15.35" x 1.25") 72-vane, D66, J Hook Iron Racing Brake Disc Replacements
AP Racing J Hook Brake Rotors – The Gold Standard in Track Day & Racing Performance
>Engineered for professional motorsport, HPDE, and dedicated track day use, AP Racing’s J Hook Brake Rotors deliver uncompromising performance, thermal stability, and consistent braking power. These two-piece, floating rotors are built to handle the extreme demands of road racing, with design features derived from over 50 years of elite competition—including Formula 1, NASCAR, and IMSA.
Unlike conventional one-piece rotors, AP Racing’s two-piece floating design features a billet aluminum hat mated to a cast iron disc via precision-engineered bobbins. This setup allows for controlled radial expansion under high heat, minimizing distortion and coning. The result? More even pad wear, a firmer pedal feel, and longer component life, even during extended lapping sessions or endurance racing. Floating hardware includes anti-knockback spring clips that reduce piston retraction while eliminating common NVH issues like rattling.
Why Choose AP Racing J Hook Rotors? Advanced Cooling, Superior Bite, Unmatched Durability
At the heart of every rotor is AP Racing’s proprietary high-carbon iron alloy, developed to withstand repeated thermal cycling without cracking or warping. Internally, directional vanes—far superior to OEM pillar or straight vane designs—maximize airflow and cooling. With 60 to 84 vanes per rotor, AP Racing achieves faster heat evacuation, reduced brake fade, and a more consistent friction surface. These rotors are left/right-specific for optimal airflow and balance.
The exclusive J Hook slot pattern offers enhanced initial bite and promotes uniform heat distribution across the rotor face, reducing pad deposits and vibration. Unlike drilled rotors or straight-slot competitors, the J Hook design provides cleaner pad transfer during bed-in and superior modulation under braking—ideal for serious drivers who demand feedback and control. Yes, you might hear a little more whirr, but you’ll gain the stopping power, consistency, and longevity your lap times demand.
Premium Components, Affordable Performance
The rotor hats are CNC-machined from 6061-T6 billet aluminum and hard anodized for strength and heat resistance. Scalloped edges under the hat further assist heat dissipation. All hardware is U.S.-made to AP Racing spec, the same quality found on pro-level racing platforms.
And while these rotors are race-proven, they’re also surprisingly cost-effective to replace. Don’t settle for cheap rotors that crack after a weekend—AP’s J Hook rings offer better durability and real long-term value. Fewer replacements mean more track time, less downtime, and peace of mind knowing you're running the best.
Used by Champions. Trusted by Experts.
From endurance racers to HPDE enthusiasts, AP Racing brake rotors are trusted worldwide for their reliability, longevity, and performance under pressure. Whether you're shaving seconds off your lap time or building a dedicated track car, the J Hook delivers a professional-grade solution that won’t let you down.
AP Racing J Hook Brake Rotors for Auto Racing, Track Days & HPDE
Why Rotor Design Matters: Heat Expansion and Floating Technology
As with most metals, iron brake discs expand significantly under heat. When temperatures rise, the disc grows radially—expanding in both diameter and circumference. Traditional one-piece rotors struggle to accommodate this natural expansion. As the outer edge pulls away from the center under heat stress, it creates a condition called “coning”—a distortion that compromises pad-to-rotor contact. This distortion can lead to uneven pad wear, brake tapering, and an inconsistent, long brake pedal.
AP Racing two-piece floating brake rotors are purpose-built to eliminate these issues. Engineered with “float” built into the disc or hat assembly, these rotors feature oblong-shaped mounting holes that allow the hardware to slide as the disc heats up. This flexibility ensures the disc runs true within the caliper under high-temperature loads, effectively reducing distortion, minimizing pad taper and stress cracks, and promoting longer component life.
Custom Mounting Hardware & Anti-Knockback Spring Clips
AP Racing rotors utilize application-specific, U.S.-made mounting hardware—not generic bolts. These premium components are the exact parts used in AP’s professional motorsport products, engineered to withstand the rigors of competitive racing.
To manage lateral disc motion that can push caliper pistons backward (known as knockback), AP Racing integrates anti-knockback spring clips on alternating bobbins—five on a ten-bolt setup, six on a twelve-bolt disc. These clips keep the aluminum hat and iron disc ring properly aligned while still allowing for radial float. Bonus: they eliminate annoying rattles and vibrations, ensuring a quieter, more refined braking experience.
High-Performance Hat Design for Heat Isolation
The disc hats in AP Racing’s two-piece floating rotors are CNC-machined from 6061-T6 billet aluminum and finished with a hard anodized coating. This high-strength aluminum alloy was selected for its ability to maintain structural integrity even at elevated temperatures. AP adds scalloped channels beneath the hat to further encourage airflow and heat evacuation from the outer disc face, minimizing thermal transfer to hubs and wheel bearings—helping reduce maintenance costs on these expensive components.
Internal Vane Engineering: Airflow Optimization & Thermal Stability
AP Racing’s internal vane design sets them apart from OEM and most aftermarket competitors. While many factory brake discs use non-directional pillar vanes (low-cost and NVH-focused), AP Racing rotors use directional vanes engineered for maximum airflow. These rotors are side-specific—meaning you’ll receive a unique left and right disc in each set—ensuring optimized cooling through strategic vane orientation and shape.
Beyond that, AP Racing rotors feature a superior vane count, typically ranging from 60 to 84 vanes, compared to 30–48 in most aftermarket rotors. After extensive CFD and thermal analysis, this high vane count was proven to:
Increase airspeed and thermal transfer
Reduce recirculation and deflection at the disc face
Minimize coning, cracking, and brake fade
Deliver more even pad contact and extended rotor life
J Hook Slot Pattern: Exclusive to AP Racing
Slots and drill holes may improve initial bite, but they also introduce “cool spots” in the rotor face—areas of uneven heating that can lead to stress risers, cracks, and pad vibration. OEM rotors often avoid this by leaving the disc face blank, but that compromises bite and brake feel.
AP Racing’s patented J Hook design, developed through rigorous R&D, solves this problem. The hooks are meticulously spaced around the disc’s circumference and from hat to edge, forming a continuous distortion path that ensures even heat distribution. This encourages uniform pad deposits during bed-in, helps reduce judder and cracking, and improves consistency under repeated high-load braking.
In addition, the J Hook slots provide more leading edges for pads to grip than traditional curved slots or blank rotors. While this might generate a mild whirring sound during braking, the benefits—more bite, cleaner bedding, better pedal feel—make it the top choice for committed racers and serious track day drivers.
Metallurgy Backed by 50+ Years of Motorsport Leadership
AP Racing's reputation is built on performance, and their proprietary iron alloy used in J Hook rotors is no exception. Drawing from over five decades of elite motorsport experience, including 750+ Formula 1 wins and widespread use across NASCAR, AP’s engineers have developed a disc alloy that excels under sustained racing temperatures and stress. Where OEM discs focus on affordability and mass production, AP Racing’s J Hook rotors are purpose-built for motorsport durability and heat resistance.
Affordable Replacement Cost: Serious Value for Serious Drivers
Even the best brake rotors are consumables. When you drive hard—especially at the track—your discs will eventually wear out. That’s why AP Racing designed their replacement iron rings to be cost-effective, allowing you to replace worn parts without breaking the bank.
Compare that to constantly buying cheap $150 rotors every weekend—rotors that can't handle the heat and need to be swapped frequently. With AP Racing’s J Hook rotors, you get longer service intervals, less downtime, and better performance over time, making them an incredibly smart long-term investment.
Proven on Track. Trusted by Champions.
Top-tier racing teams rely on AP Racing J Hook rotors for one reason: they perform under pressure. Whether you're running time trials, attending HPDE events, or competing in wheel-to-wheel racing, these rotors offer professional-grade reliability, safety, and performance.
Bedding and Preparation of AP Racing J Hook Discs
Properly preparing your new brake discs before heavy use is extremely important. The goal of bedding-in your brake pads and discs is to mate them together properly and prepare them for heavy use. When prepared properly, or bed-in, your pads will transfer a thin layer of material to the disc face (transfer layer). The pads in your caliper will then actually ride on that thin layer of pad material you’ve put down on the rotor, rather than rubbing directly on the iron rotor face. A good transfer layer is going to give you superior brake pedal feel, less noise, superior pad wear, and lower the chances of cracking your discs.
Important Notes- PLEASE READ! First, make sure you are on a closed course to perform a proper bed-in. Do NOT perform the procedure on public roads. You need a stretch of asphalt with long straights, good visibility, and no potential obstructions. Make sure you are in a position to safely and repeatedly attain the necessary speeds to perform the bed-in procedure. A controlled racetrack is the best place to perform this procedure. AP Racing and Competition Motorsport in no way suggest or condone speeding on public roads or breaking the law in your car, nor do we take responsibility for any damage or injury that occurs as a result of using our product or these procedures. You are performing the bed-in procedure at your own risk.
During these procedures, it’s critical that you never come to a complete stop with your foot on the brake pedal. If you have brake ducts on your car, you may want to block them off to allow your brake system to heat up easily. The procedure outlined below is a generic procedure for most types of mild race pad. Please check your pad manufacturer’s recommended bed-in procedure.
Accelerate to approximately 60mph and then decelerate down to 5 mph. If your car has ABS, you should try to hold the brakes at a point just before ABS intervention.
Once the car slows to 5mph, immediately accelerate back up to about 60mph, and brake again to roughly 5mph.
Repeat this series of stopping and accelerating 8 to 10 times. Again, do not come to a complete stop with your foot on the brake pedal.
Cool the brake system down by cruising at 45mph+ for 5 to 10 minutes.
Visually inspect your discs. They should be a blue/grey color (instead of shiny silver), and have an even layer of pad material across and around the entire rotor face.
If the AP Racing rotors don’t have a layer of pad material on them, perform another series of stops in the manner outlined above.

AP Racing
AP Racing 380x30mm Replacement Rear Brake Rotor Rings for Porsche (OEM Iron)
$1,096.00
AP Racing J Hook 380x30mm Replacement Rear Brake Rotor Rings
This kit is two replacement rotor discs and new installation hardware only. Center hats are not included. Replacement rotor rings for AP Racing 13.01.20018.
Fits The Following Cars (w/ OEM iron rotors):
Porsche 992 GT3 (Rear)
Porsche 992 GT3RS (Rear)
Porsche 718/982 GT4RS (Rear)
Porsche 991 GT2RS/GT3/GT3RS (Rear)
Porsche 981 GT4 (Rear)
Sold/priced per pair of rotor rings (including hardware).
AP Racing J Hook Brake Rotors – The Gold Standard in Track Day & Racing Performance
Engineered for professional motorsport, HPDE, and dedicated track day use, AP Racing’s J Hook Brake Rotors deliver uncompromising performance, thermal stability, and consistent braking power. These two-piece, floating rotors are built to handle the extreme demands of road racing, with design features derived from over 50 years of elite competition—including Formula 1, NASCAR, and IMSA.
Unlike conventional one-piece rotors, AP Racing’s two-piece floating design features a billet aluminum hat mated to a cast iron disc via precision-engineered bobbins. This setup allows for controlled radial expansion under high heat, minimizing distortion and coning. The result? More even pad wear, a firmer pedal feel, and longer component life, even during extended lapping sessions or endurance racing. Floating hardware includes anti-knockback spring clips that reduce piston retraction while eliminating common NVH issues like rattling.
Why Choose AP Racing J Hook Rotors? Advanced Cooling, Superior Bite, Unmatched Durability
At the heart of every rotor is AP Racing’s proprietary high-carbon iron alloy, developed to withstand repeated thermal cycling without cracking or warping. Internally, directional vanes—far superior to OEM pillar or straight vane designs—maximize airflow and cooling. With 60 to 84 vanes per rotor, AP Racing achieves faster heat evacuation, reduced brake fade, and a more consistent friction surface. These rotors are left/right-specific for optimal airflow and balance.
The exclusive J Hook slot pattern offers enhanced initial bite and promotes uniform heat distribution across the rotor face, reducing pad deposits and vibration. Unlike drilled rotors or straight-slot competitors, the J Hook design provides cleaner pad transfer during bed-in and superior modulation under braking—ideal for serious drivers who demand feedback and control. Yes, you might hear a little more whirr, but you’ll gain the stopping power, consistency, and longevity your lap times demand.
Premium Components, Affordable Performance
The rotor hats are CNC-machined from 6061-T6 billet aluminum and hard anodized for strength and heat resistance. Scalloped edges under the hat further assist heat dissipation. All hardware is U.S.-made to AP Racing spec, the same quality found on pro-level racing platforms.
And while these rotors are race-proven, they’re also surprisingly cost-effective to replace. Don’t settle for cheap rotors that crack after a weekend—AP’s J Hook rings offer better durability and real long-term value. Fewer replacements mean more track time, less downtime, and peace of mind knowing you're running the best.
Used by Champions. Trusted by Experts.
From endurance racers to HPDE enthusiasts, AP Racing brake rotors are trusted worldwide for their reliability, longevity, and performance under pressure. Whether you're shaving seconds off your lap time or building a dedicated track car, the J Hook delivers a professional-grade solution that won’t let you down.
AP Racing J Hook Brake Rotors for Auto Racing, Track Days & HPDE
Why Rotor Design Matters: Heat Expansion and Floating Technology
As with most metals, iron brake discs expand significantly under heat. When temperatures rise, the disc grows radially—expanding in both diameter and circumference. Traditional one-piece rotors struggle to accommodate this natural expansion. As the outer edge pulls away from the center under heat stress, it creates a condition called “coning”—a distortion that compromises pad-to-rotor contact. This distortion can lead to uneven pad wear, brake tapering, and an inconsistent, long brake pedal.
AP Racing two-piece floating brake rotors are purpose-built to eliminate these issues. Engineered with “float” built into the disc or hat assembly, these rotors feature oblong-shaped mounting holes that allow the hardware to slide as the disc heats up. This flexibility ensures the disc runs true within the caliper under high-temperature loads, effectively reducing distortion, minimizing pad taper and stress cracks, and promoting longer component life.
Custom Mounting Hardware & Anti-Knockback Spring Clips
AP Racing rotors utilize application-specific, U.S.-made mounting hardware—not generic bolts. These premium components are the exact parts used in AP’s professional motorsport products, engineered to withstand the rigors of competitive racing.
To manage lateral disc motion that can push caliper pistons backward (known as knockback), AP Racing integrates anti-knockback spring clips on alternating bobbins—five on a ten-bolt setup, six on a twelve-bolt disc. These clips keep the aluminum hat and iron disc ring properly aligned while still allowing for radial float. Bonus: they eliminate annoying rattles and vibrations, ensuring a quieter, more refined braking experience.
High-Performance Hat Design for Heat Isolation
The disc hats in AP Racing’s two-piece floating rotors are CNC-machined from 6061-T6 billet aluminum and finished with a hard anodized coating. This high-strength aluminum alloy was selected for its ability to maintain structural integrity even at elevated temperatures. AP adds scalloped channels beneath the hat to further encourage airflow and heat evacuation from the outer disc face, minimizing thermal transfer to hubs and wheel bearings—helping reduce maintenance costs on these expensive components.
Internal Vane Engineering: Airflow Optimization & Thermal Stability
AP Racing’s internal vane design sets them apart from OEM and most aftermarket competitors. While many factory brake discs use non-directional pillar vanes (low-cost and NVH-focused), AP Racing rotors use directional vanes engineered for maximum airflow. These rotors are side-specific—meaning you’ll receive a unique left and right disc in each set—ensuring optimized cooling through strategic vane orientation and shape.
Beyond that, AP Racing rotors feature a superior vane count, typically ranging from 60 to 84 vanes, compared to 30–48 in most aftermarket rotors. After extensive CFD and thermal analysis, this high vane count was proven to:
Increase airspeed and thermal transfer
Reduce recirculation and deflection at the disc face
Minimize coning, cracking, and brake fade
Deliver more even pad contact and extended rotor life
J Hook Slot Pattern: Exclusive to AP Racing
Slots and drill holes may improve initial bite, but they also introduce “cool spots” in the rotor face—areas of uneven heating that can lead to stress risers, cracks, and pad vibration. OEM rotors often avoid this by leaving the disc face blank, but that compromises bite and brake feel.
AP Racing’s patented J Hook design, developed through rigorous R&D, solves this problem. The hooks are meticulously spaced around the disc’s circumference and from hat to edge, forming a continuous distortion path that ensures even heat distribution. This encourages uniform pad deposits during bed-in, helps reduce judder and cracking, and improves consistency under repeated high-load braking.
In addition, the J Hook slots provide more leading edges for pads to grip than traditional curved slots or blank rotors. While this might generate a mild whirring sound during braking, the benefits—more bite, cleaner bedding, better pedal feel—make it the top choice for committed racers and serious track day drivers.
Metallurgy Backed by 50+ Years of Motorsport Leadership
AP Racing's reputation is built on performance, and their proprietary iron alloy used in J Hook rotors is no exception. Drawing from over five decades of elite motorsport experience, including 750+ Formula 1 wins and widespread use across NASCAR, AP’s engineers have developed a disc alloy that excels under sustained racing temperatures and stress. Where OEM discs focus on affordability and mass production, AP Racing’s J Hook rotors are purpose-built for motorsport durability and heat resistance.
Affordable Replacement Cost: Serious Value for Serious Drivers
Even the best brake rotors are consumables. When you drive hard—especially at the track—your discs will eventually wear out. That’s why AP Racing designed their replacement iron rings to be cost-effective, allowing you to replace worn parts without breaking the bank.
Compare that to constantly buying cheap $150 rotors every weekend—rotors that can't handle the heat and need to be swapped frequently. With AP Racing’s J Hook rotors, you get longer service intervals, less downtime, and better performance over time, making them an incredibly smart long-term investment.
Proven on Track. Trusted by Champions.
Top-tier racing teams rely on AP Racing J Hook rotors for one reason: they perform under pressure. Whether you're running time trials, attending HPDE events, or competing in wheel-to-wheel racing, these rotors offer professional-grade reliability, safety, and performance.
Bedding and Preparation of AP Racing J Hook Discs
Properly preparing your new brake discs before heavy use is extremely important. The goal of bedding-in your brake pads and discs is to mate them together properly and prepare them for heavy use. When prepared properly, or bed-in, your pads will transfer a thin layer of material to the disc face (transfer layer). The pads in your caliper will then actually ride on that thin layer of pad material you’ve put down on the rotor, rather than rubbing directly on the iron rotor face. A good transfer layer is going to give you superior brake pedal feel, less noise, superior pad wear, and lower the chances of cracking your discs.
Important Notes- PLEASE READ! First, make sure you are on a closed course to perform a proper bed-in. Do NOT perform the procedure on public roads. You need a stretch of asphalt with long straights, good visibility, and no potential obstructions. Make sure you are in a position to safely and repeatedly attain the necessary speeds to perform the bed-in procedure. A controlled racetrack is the best place to perform this procedure. AP Racing and Competition Motorsport in no way suggest or condone speeding on public roads or breaking the law in your car, nor do we take responsibility for any damage or injury that occurs as a result of using our product or these procedures. You are performing the bed-in procedure at your own risk.
During these procedures, it’s critical that you never come to a complete stop with your foot on the brake pedal. If you have brake ducts on your car, you may want to block them off to allow your brake system to heat up easily. The procedure outlined below is a generic procedure for most types of mild race pad. Please check your pad manufacturer’s recommended bed-in procedure.
Accelerate to approximately 60mph and then decelerate down to 5 mph. If your car has ABS, you should try to hold the brakes at a point just before ABS intervention.
Once the car slows to 5mph, immediately accelerate back up to about 60mph, and brake again to roughly 5mph.
Repeat this series of stopping and accelerating 8 to 10 times. Again, do not come to a complete stop with your foot on the brake pedal.
Cool the brake system down by cruising at 45mph+ for 5 to 10 minutes.
Visually inspect your discs. They should be a blue/grey color (instead of shiny silver), and have an even layer of pad material across and around the entire rotor face.
If the AP Racing rotors don’t have a layer of pad material on them, perform another series of stops in the manner outlined above.

AP Racing
AP Racing 408x34mm Replacement Front Brake Rotor Rings for Porsche (OEM PCCB or Iron)
$1,596.00
AP Racing 408x34mm J Hook Disc Replacement Front Floating Racing Brake Rotor Rings
Fits the following cars which use AP Racing 13.01.20038 or 13.01.20050 (w/ OEM Iron Rotors or PCCB Rotors) - Center hat Excluded, rotor discs and hardware only. Replacement Disc Only For AP Racing 13.01.20038 or 13.01.20050
Porsche 992 GT3 PCCB/Iron (Front)
Porsche 992 GT3RS PCCB/Iron (Front)
Porsche GT4RS PCCB/Iron (Front)
Sold/priced per pair of replacement rotor rings with hardware.
408mm x 34mm (16.06" x 1.34") 84 Wave Vane, D62, J Hook Iron Racing Brake Disc
We are introducing a new internal vane technology in our front 2-piece discs for the 992 GT3. It is called the Sinusoidal Vane, which AP sometimes refers to internally as the 'Wave' Vane for obvious reasons as you’ll see below. This tech is something that has helped AP Racing brake systems win championships in international GT racing, as well as multiple NASCAR Cup championships here in North America. As one of the most desirable track weapons on the planet, we wanted the 992 GT3 to be the first production car application for this technology in North America. Just as AP Racing's Radi-CAL calipers set a new benchmark for caliper stability, cooling, and durability, the Sinusoidal Vanes have done the same for iron racing discs.
The concept for this disc design originated in NASCAR Cup. Up until the debut of the Next Gen car (for which AP/Essex are supplying the spec brake package), we were cramming our brake systems inside tiny 15” wheels. Trying to squeeze adequate brake thermal mass into a wheel that small is incredibly challenging, particularly when you have a 1,000 HP and 3,000 pounds mashing on them every few seconds from 200 mph…for hours on end! In a wheel that small, there isn’t anywhere for the heat to go, and the durability of every component is crucial. We were constantly looking for ways to provide the Cup teams with increased durability, stability, and cooling, and that’s what led AP to this technology.
Benefits of the Wave Vane disc technology vs. traditional curved vanes:
Increased thermal stability- Wild temperature swings are what causes discs to crack. When you stand on the brakes for an approaching corner, your disc temperatures skyrocket and the iron expands. As you travel down the subsequent straight, the discs are blasted with cooling air. The longer the straight and the higher the speed, the greater the temperature drop, and the further the iron contracts. This expansion and contraction cycle places a huge amount of stress on the iron and is what causes them to eventually crack. That’s why tracks with relatively slow corners at the end of high-speed straights, followed by another long straight, decimate brake discs (think Watkins Glen or Road America). In an ideal world, once you brought your discs up to race temps, you would keep them at a constant temperature for the entire session. The Sinusoidal Vane brings the discs closer to that goal by decreasing the difference between the maximum and minimum disc temperature by as much as 35%. That means a less dramatic temperature swing and greater crack resistance and durability.
Reduced maximum disc temperatures by 10%+: Not only are temperature swings less intense with the Wave Vane, the maximum temperatures reached are substantially lower. For example, in one NASCAR test the Wave Vane discs showed a peak temp of 1328F and a minimum temp of 1085F (delta of 243F), while the traditional curved vanes maxed out at 1490F and a min of 1121F (delta of 369F). Not only was the difference between min and max more subdued, the max temperature reached by the Wave Vane disc was 162F lower!
Increased cooling surface area- Each of the internal Wave Vanes has a larger cooling surface area vs. a traditional curved vane.
Greater support for the disc face- A disc’s internal vane structure provides the support lattice behind the disc face. Having many internal vanes impacts airspeed and heat transfer through the disc, reduces air recirculation between vanes, and reduces deflection at the disc face. In practical terms, a disc with a high number of vanes is more thermally stable, maintains more even contact with the brake pads (which reduces uneven pad deposits/judder), and is less prone to distortion. In summary, the Wave Vane design provides even greater support for the disc face than AP’s standard curved vane designs.
Reduced weight- The Wave Vane design provides a slight unsprung weight reduction vs. a similar disc with curved internal vanes.
AP Racing J Hook Brake Rotors – The Gold Standard in Track Day & Racing Performance
Engineered for professional motorsport, HPDE, and dedicated track day use, AP Racing’s J Hook Brake Rotors deliver uncompromising performance, thermal stability, and consistent braking power. These two-piece, floating rotors are built to handle the extreme demands of road racing, with design features derived from over 50 years of elite competition—including Formula 1, NASCAR, and IMSA.
Unlike conventional one-piece rotors, AP Racing’s two-piece floating design features a billet aluminum hat mated to a cast iron disc via precision-engineered bobbins. This setup allows for controlled radial expansion under high heat, minimizing distortion and coning. The result? More even pad wear, a firmer pedal feel, and longer component life, even during extended lapping sessions or endurance racing. Floating hardware includes anti-knockback spring clips that reduce piston retraction while eliminating common NVH issues like rattling.
Why Choose AP Racing J Hook Rotors? Advanced Cooling, Superior Bite, Unmatched Durability
At the heart of every rotor is AP Racing’s proprietary high-carbon iron alloy, developed to withstand repeated thermal cycling without cracking or warping. Internally, directional vanes—far superior to OEM pillar or straight vane designs—maximize airflow and cooling. With 60 to 84 vanes per rotor, AP Racing achieves faster heat evacuation, reduced brake fade, and a more consistent friction surface. These rotors are left/right-specific for optimal airflow and balance.
The exclusive J Hook slot pattern offers enhanced initial bite and promotes uniform heat distribution across the rotor face, reducing pad deposits and vibration. Unlike drilled rotors or straight-slot competitors, the J Hook design provides cleaner pad transfer during bed-in and superior modulation under braking—ideal for serious drivers who demand feedback and control. Yes, you might hear a little more whirr, but you’ll gain the stopping power, consistency, and longevity your lap times demand.
Premium Components, Affordable Performance
The rotor hats are CNC-machined from 6061-T6 billet aluminum and hard anodized for strength and heat resistance. Scalloped edges under the hat further assist heat dissipation. All hardware is U.S.-made to AP Racing spec, the same quality found on pro-level racing platforms.
And while these rotors are race-proven, they’re also surprisingly cost-effective to replace. Don’t settle for cheap rotors that crack after a weekend—AP’s J Hook rings offer better durability and real long-term value. Fewer replacements mean more track time, less downtime, and peace of mind knowing you're running the best.
Used by Champions. Trusted by Experts.
From endurance racers to HPDE enthusiasts, AP Racing brake rotors are trusted worldwide for their reliability, longevity, and performance under pressure. Whether you're shaving seconds off your lap time or building a dedicated track car, the J Hook delivers a professional-grade solution that won’t let you down.
AP Racing J Hook Brake Rotors for Auto Racing, Track Days & HPDE
Why Rotor Design Matters: Heat Expansion and Floating Technology
As with most metals, iron brake discs expand significantly under heat. When temperatures rise, the disc grows radially—expanding in both diameter and circumference. Traditional one-piece rotors struggle to accommodate this natural expansion. As the outer edge pulls away from the center under heat stress, it creates a condition called “coning”—a distortion that compromises pad-to-rotor contact. This distortion can lead to uneven pad wear, brake tapering, and an inconsistent, long brake pedal.
AP Racing two-piece floating brake rotors are purpose-built to eliminate these issues. Engineered with “float” built into the disc or hat assembly, these rotors feature oblong-shaped mounting holes that allow the hardware to slide as the disc heats up. This flexibility ensures the disc runs true within the caliper under high-temperature loads, effectively reducing distortion, minimizing pad taper and stress cracks, and promoting longer component life.
Custom Mounting Hardware & Anti-Knockback Spring Clips
AP Racing rotors utilize application-specific, U.S.-made mounting hardware—not generic bolts. These premium components are the exact parts used in AP’s professional motorsport products, engineered to withstand the rigors of competitive racing.
To manage lateral disc motion that can push caliper pistons backward (known as knockback), AP Racing integrates anti-knockback spring clips on alternating bobbins—five on a ten-bolt setup, six on a twelve-bolt disc. These clips keep the aluminum hat and iron disc ring properly aligned while still allowing for radial float. Bonus: they eliminate annoying rattles and vibrations, ensuring a quieter, more refined braking experience.
High-Performance Hat Design for Heat Isolation
The disc hats in AP Racing’s two-piece floating rotors are CNC-machined from 6061-T6 billet aluminum and finished with a hard anodized coating. This high-strength aluminum alloy was selected for its ability to maintain structural integrity even at elevated temperatures. AP adds scalloped channels beneath the hat to further encourage airflow and heat evacuation from the outer disc face, minimizing thermal transfer to hubs and wheel bearings—helping reduce maintenance costs on these expensive components.
Internal Vane Engineering: Airflow Optimization & Thermal Stability
AP Racing’s internal vane design sets them apart from OEM and most aftermarket competitors. While many factory brake discs use non-directional pillar vanes (low-cost and NVH-focused), AP Racing rotors use directional vanes engineered for maximum airflow. These rotors are side-specific—meaning you’ll receive a unique left and right disc in each set—ensuring optimized cooling through strategic vane orientation and shape.
Beyond that, AP Racing rotors feature a superior vane count, typically ranging from 60 to 84 vanes, compared to 30–48 in most aftermarket rotors. After extensive CFD and thermal analysis, this high vane count was proven to:
Increase airspeed and thermal transfer
Reduce recirculation and deflection at the disc face
Minimize coning, cracking, and brake fade
Deliver more even pad contact and extended rotor life
J Hook Slot Pattern: Exclusive to AP Racing
Slots and drill holes may improve initial bite, but they also introduce “cool spots” in the rotor face—areas of uneven heating that can lead to stress risers, cracks, and pad vibration. OEM rotors often avoid this by leaving the disc face blank, but that compromises bite and brake feel.
AP Racing’s patented J Hook design, developed through rigorous R&D, solves this problem. The hooks are meticulously spaced around the disc’s circumference and from hat to edge, forming a continuous distortion path that ensures even heat distribution. This encourages uniform pad deposits during bed-in, helps reduce judder and cracking, and improves consistency under repeated high-load braking.
In addition, the J Hook slots provide more leading edges for pads to grip than traditional curved slots or blank rotors. While this might generate a mild whirring sound during braking, the benefits—more bite, cleaner bedding, better pedal feel—make it the top choice for committed racers and serious track day drivers.
Metallurgy Backed by 50+ Years of Motorsport Leadership
AP Racing's reputation is built on performance, and their proprietary iron alloy used in J Hook rotors is no exception. Drawing from over five decades of elite motorsport experience, including 750+ Formula 1 wins and widespread use across NASCAR, AP’s engineers have developed a disc alloy that excels under sustained racing temperatures and stress. Where OEM discs focus on affordability and mass production, AP Racing’s J Hook rotors are purpose-built for motorsport durability and heat resistance.
Affordable Replacement Cost: Serious Value for Serious Drivers
Even the best brake rotors are consumables. When you drive hard—especially at the track—your discs will eventually wear out. That’s why AP Racing designed their replacement iron rings to be cost-effective, allowing you to replace worn parts without breaking the bank.
Compare that to constantly buying cheap $150 rotors every weekend—rotors that can't handle the heat and need to be swapped frequently. With AP Racing’s J Hook rotors, you get longer service intervals, less downtime, and better performance over time, making them an incredibly smart long-term investment.
Proven on Track. Trusted by Champions.
Top-tier racing teams rely on AP Racing J Hook rotors for one reason: they perform under pressure. Whether you're running time trials, attending HPDE events, or competing in wheel-to-wheel racing, these rotors offer professional-grade reliability, safety, and performance.
Bedding and preparation of AP Racing J Hook Disc
Properly preparing your new brake discs before heavy use is extremely important. The goal of bedding-in your brake pads and discs is to mate them together properly and prepare them for heavy use. When prepared properly, or bed-in, your pads will transfer a thin layer of material to the disc face (transfer layer). The pads in your caliper will then actually ride on that thin layer of pad material you’ve put down on the rotor, rather than rubbing directly on the iron rotor face. A good transfer layer is going to give you superior brake pedal feel, less noise, superior pad wear, and lower the chances of cracking your discs.
Important Notes- PLEASE READ! First, make sure you are on a closed course to perform a proper bed-in. Do NOT perform the procedure on public roads. You need a stretch of asphalt with long straights, good visibility, and no potential obstructions. Make sure you are in a position to safely and repeatedly attain the necessary speeds to perform the bed-in procedure. A controlled racetrack is the best place to perform this procedure. AP Racing and Competition Motorsport in no way suggest or condone speeding on public roads or breaking the law in your car, nor do we take responsibility for any damage or injury that occurs as a result of using our product or these procedures. You are performing the bed-in procedure at your own risk.
During these procedures, it’s critical that you never come to a complete stop with your foot on the brake pedal. If you have brake ducts on your car, you may want to block them off to allow your brake system to heat up easily. The procedure outlined below is a generic procedure for most types of mild race pad. Please check your pad manufacturer’s recommended bed-in procedure.
Accelerate to approximately 60mph and then decelerate down to 5 mph. If your car has ABS, you should try to hold the brakes at a point just before ABS intervention.
Once the car slows to 5mph, immediately accelerate back up to about 60mph, and brake again to roughly 5mph.
Repeat this series of stopping and accelerating 8 to 10 times. Again, do not come to a complete stop with your foot on the brake pedal.
Cool the brake system down by cruising at 45mph+ for 5 to 10 minutes.
Visually inspect your discs. They should be a blue/grey color (instead of shiny silver), and have an even layer of pad material across and around the entire rotor face.
If the AP Racing rotors don’t have a layer of pad material on them, perform another series of stops in the manner outlined above.

AP Racing
AP Racing 380x30mm 2-piece J Hook Rear Brake Rotors for Porsche (OEM Iron)
$2,099.00
AP Racing 380x30mm 2-piece J Hook Rear Brake Rotors for Porsche (OEM Iron)
Fit The Following Cars (w/ OEM Iron Rotors)
Porsche 992 GT3 (Rear)
Porsche 992 GT3RS (Rear)
Porsche 718/982 GT4RS (Rear)
Porsche 991 GT2RS/GT3/GT3RS (Rear)
Porsche 981 GT4 (Rear)
Sold/priced per pair.
AP Racing 2-piece Competition J Hook rear disc pair for 991.1 & 991.2 GT3 (including GT3RS), 992 GT3, and 718 GT4 and GT4 RS with iron discs
380x30mm (14.96" x 1.18") 72 Vane, D67 radial depth
Huge increase in airflow, cooling capacity, and durability vs. OEM discs
Saves 3-4 lbs. unsprung weight per side
Retains full parking brake functionality
Designed for: club racing, time trial, auto-x, HPDE
Works with OEM calipers, no modifications required
Ultralight, fully floating, anodized billet aluminum hat with float control/anti-rattle clips
Sold/priced per pair.
AP Racing J Hook Brake Rotors – The Gold Standard in Track Day & Racing Performance
Engineered for professional motorsport, HPDE, and dedicated track day use, AP Racing’s J Hook Brake Rotors deliver uncompromising performance, thermal stability, and consistent braking power. These two-piece, floating rotors are built to handle the extreme demands of road racing, with design features derived from over 50 years of elite competition—including Formula 1, NASCAR, and IMSA.
Unlike conventional one-piece rotors, AP Racing’s two-piece floating design features a billet aluminum hat mated to a cast iron disc via precision-engineered bobbins. This setup allows for controlled radial expansion under high heat, minimizing distortion and coning. The result? More even pad wear, a firmer pedal feel, and longer component life, even during extended lapping sessions or endurance racing. Floating hardware includes anti-knockback spring clips that reduce piston retraction while eliminating common NVH issues like rattling.
Why Choose AP Racing J Hook Rotors? Advanced Cooling, Superior Bite, Unmatched Durability
At the heart of every rotor is AP Racing’s proprietary high-carbon iron alloy, developed to withstand repeated thermal cycling without cracking or warping. Internally, directional vanes—far superior to OEM pillar or straight vane designs—maximize airflow and cooling. With 60 to 84 vanes per rotor, AP Racing achieves faster heat evacuation, reduced brake fade, and a more consistent friction surface. These rotors are left/right-specific for optimal airflow and balance.
The exclusive J Hook slot pattern offers enhanced initial bite and promotes uniform heat distribution across the rotor face, reducing pad deposits and vibration. Unlike drilled rotors or straight-slot competitors, the J Hook design provides cleaner pad transfer during bed-in and superior modulation under braking—ideal for serious drivers who demand feedback and control. Yes, you might hear a little more whirr, but you’ll gain the stopping power, consistency, and longevity your lap times demand.
Premium Components, Affordable Performance
The rotor hats are CNC-machined from 6061-T6 billet aluminum and hard anodized for strength and heat resistance. Scalloped edges under the hat further assist heat dissipation. All hardware is U.S.-made to AP Racing spec, the same quality found on pro-level racing platforms.
And while these rotors are race-proven, they’re also surprisingly cost-effective to replace. Don’t settle for cheap rotors that crack after a weekend—AP’s J Hook rings offer better durability and real long-term value. Fewer replacements mean more track time, less downtime, and peace of mind knowing you're running the best.
Used by Champions. Trusted by Experts.
From endurance racers to HPDE enthusiasts, AP Racing brake rotors are trusted worldwide for their reliability, longevity, and performance under pressure. Whether you're shaving seconds off your lap time or building a dedicated track car, the J Hook delivers a professional-grade solution that won’t let you down.
AP Racing J Hook Brake Rotors for Auto Racing, Track Days & HPDE
Why Rotor Design Matters: Heat Expansion and Floating Technology
As with most metals, iron brake discs expand significantly under heat. When temperatures rise, the disc grows radially—expanding in both diameter and circumference. Traditional one-piece rotors struggle to accommodate this natural expansion. As the outer edge pulls away from the center under heat stress, it creates a condition called “coning”—a distortion that compromises pad-to-rotor contact. This distortion can lead to uneven pad wear, brake tapering, and an inconsistent, long brake pedal.
AP Racing two-piece floating brake rotors are purpose-built to eliminate these issues. Engineered with “float” built into the disc or hat assembly, these rotors feature oblong-shaped mounting holes that allow the hardware to slide as the disc heats up. This flexibility ensures the disc runs true within the caliper under high-temperature loads, effectively reducing distortion, minimizing pad taper and stress cracks, and promoting longer component life.
Custom Mounting Hardware & Anti-Knockback Spring Clips
AP Racing rotors utilize application-specific, U.S.-made mounting hardware—not generic bolts. These premium components are the exact parts used in AP’s professional motorsport products, engineered to withstand the rigors of competitive racing.
To manage lateral disc motion that can push caliper pistons backward (known as knockback), AP Racing integrates anti-knockback spring clips on alternating bobbins—five on a ten-bolt setup, six on a twelve-bolt disc. These clips keep the aluminum hat and iron disc ring properly aligned while still allowing for radial float. Bonus: they eliminate annoying rattles and vibrations, ensuring a quieter, more refined braking experience.
High-Performance Hat Design for Heat Isolation
The disc hats in AP Racing’s two-piece floating rotors are CNC-machined from 6061-T6 billet aluminum and finished with a hard anodized coating. This high-strength aluminum alloy was selected for its ability to maintain structural integrity even at elevated temperatures. AP adds scalloped channels beneath the hat to further encourage airflow and heat evacuation from the outer disc face, minimizing thermal transfer to hubs and wheel bearings—helping reduce maintenance costs on these expensive components.
Internal Vane Engineering: Airflow Optimization & Thermal Stability
AP Racing’s internal vane design sets them apart from OEM and most aftermarket competitors. While many factory brake discs use non-directional pillar vanes (low-cost and NVH-focused), AP Racing rotors use directional vanes engineered for maximum airflow. These rotors are side-specific—meaning you’ll receive a unique left and right disc in each set—ensuring optimized cooling through strategic vane orientation and shape.
Beyond that, AP Racing rotors feature a superior vane count, typically ranging from 60 to 84 vanes, compared to 30–48 in most aftermarket rotors. After extensive CFD and thermal analysis, this high vane count was proven to:
Increase airspeed and thermal transfer
Reduce recirculation and deflection at the disc face
Minimize coning, cracking, and brake fade
Deliver more even pad contact and extended rotor life
J Hook Slot Pattern: Exclusive to AP Racing
Slots and drill holes may improve initial bite, but they also introduce “cool spots” in the rotor face—areas of uneven heating that can lead to stress risers, cracks, and pad vibration. OEM rotors often avoid this by leaving the disc face blank, but that compromises bite and brake feel.
AP Racing’s patented J Hook design, developed through rigorous R&D, solves this problem. The hooks are meticulously spaced around the disc’s circumference and from hat to edge, forming a continuous distortion path that ensures even heat distribution. This encourages uniform pad deposits during bed-in, helps reduce judder and cracking, and improves consistency under repeated high-load braking.
In addition, the J Hook slots provide more leading edges for pads to grip than traditional curved slots or blank rotors. While this might generate a mild whirring sound during braking, the benefits—more bite, cleaner bedding, better pedal feel—make it the top choice for committed racers and serious track day drivers.
Metallurgy Backed by 50+ Years of Motorsport Leadership
AP Racing's reputation is built on performance, and their proprietary iron alloy used in J Hook rotors is no exception. Drawing from over five decades of elite motorsport experience, including 750+ Formula 1 wins and widespread use across NASCAR, AP’s engineers have developed a disc alloy that excels under sustained racing temperatures and stress. Where OEM discs focus on affordability and mass production, AP Racing’s J Hook rotors are purpose-built for motorsport durability and heat resistance.
Affordable Replacement Cost: Serious Value for Serious Drivers
Even the best brake rotors are consumables. When you drive hard—especially at the track—your discs will eventually wear out. That’s why AP Racing designed their replacement iron rings to be cost-effective, allowing you to replace worn parts without breaking the bank.
Compare that to constantly buying cheap $150 rotors every weekend—rotors that can't handle the heat and need to be swapped frequently. With AP Racing’s J Hook rotors, you get longer service intervals, less downtime, and better performance over time, making them an incredibly smart long-term investment.
Proven on Track. Trusted by Champions.
Top-tier racing teams rely on AP Racing J Hook rotors for one reason: they perform under pressure. Whether you're running time trials, attending HPDE events, or competing in wheel-to-wheel racing, these rotors offer professional-grade reliability, safety, and performance.
Bedding and preparation of AP Racing J Hook Disc
Properly preparing your new brake discs before heavy use is extremely important. The goal of bedding-in your brake pads and discs is to mate them together properly and prepare them for heavy use. When prepared properly, or bed-in, your pads will transfer a thin layer of material to the disc face (transfer layer). The pads in your caliper will then actually ride on that thin layer of pad material you’ve put down on the rotor, rather than rubbing directly on the iron rotor face. A good transfer layer is going to give you superior brake pedal feel, less noise, superior pad wear, and lower the chances of cracking your discs.
Important Notes- PLEASE READ! First, make sure you are on a closed course to perform a proper bed-in. Do NOT perform the procedure on public roads. You need a stretch of asphalt with long straights, good visibility, and no potential obstructions. Make sure you are in a position to safely and repeatedly attain the necessary speeds to perform the bed-in procedure. A controlled racetrack is the best place to perform this procedure. AP Racing and Competition Motorsport in no way suggest or condone speeding on public roads or breaking the law in your car, nor do we take responsibility for any damage or injury that occurs as a result of using our product or these procedures. You are performing the bed-in procedure at your own risk.
During these procedures, it’s critical that you never come to a complete stop with your foot on the brake pedal. If you have brake ducts on your car, you may want to block them off to allow your brake system to heat up easily. The procedure outlined below is a generic procedure for most types of mild race pad. Please check your pad manufacturer’s recommended bed-in procedure.
Accelerate to approximately 60mph and then decelerate down to 5 mph. If your car has ABS, you should try to hold the brakes at a point just before ABS intervention.
Once the car slows to 5mph, immediately accelerate back up to about 60mph, and brake again to roughly 5mph.
Repeat this series of stopping and accelerating 8 to 10 times. Again, do not come to a complete stop with your foot on the brake pedal.
Cool the brake system down by cruising at 45mph+ for 5 to 10 minutes.
Visually inspect your discs. They should be a blue/grey color (instead of shiny silver), and have an even layer of pad material across and around the entire rotor face.
If the AP Racing rotors don’t have a layer of pad material on them, perform another series of stops in the manner outlined above.

AP Racing
AP Racing 390x32mm 2-piece Competition J Hook Rear Brake Rotors - Porsche (OEM PCCB)
$2,599.00
AP Racing 390x32mm 2-piece J Hook Rear Brake Rotors - Porsche (OEM PCCB)
Fit The Following Cars (w/ OEM PCCB Rotors)
Porsche 992 GT3 (Rear)
Porsche 992 GT3RS (Rear)
Porsche 718/982 GT4RS (Rear)
Porsche 991 GT2RS/GT3/GT3RS (Rear)
Porsche 981 GT4 (Rear)
Sold/priced per pair.
AP Racing 2-piece Competition J Hook rear iron disc pair for 991/992 GT3/RS and 718 GT4/Spyder RS to replace PCCB discs.
390 x 32mm (15.35" x 1.26")
Huge increase in airflow, cooling capacity, and durability vs. OEM PCCB discs
Drastically less expense long-term running costs vs. PCCB
Must useGT3/RS Iron disc pad shape used in OEM iron system (not compatible with OE PCCB Pad shape)
Allows normal function of OEM parking brake
100% more internal cooling vanes vs the OEM PCCB's
Same weight as OEM 380 x 34mm iron discs, despite larger size
Designed for: club racing, time trial, auto-x, HPDE
Works with OEM calipers and wheels, no modifications required
Ultralight, fully floating, anodized billet aluminum hat with float control/anti-rattle clips
AP Racing J Hook Brake Rotors – The Gold Standard in Track Day & Racing Performance
Engineered for professional motorsport, HPDE, and dedicated track day use, AP Racing’s J Hook Brake Rotors deliver uncompromising performance, thermal stability, and consistent braking power. These two-piece, floating rotors are built to handle the extreme demands of road racing, with design features derived from over 50 years of elite competition—including Formula 1, NASCAR, and IMSA.
Unlike conventional one-piece rotors, AP Racing’s two-piece floating design features a billet aluminum hat mated to a cast iron disc via precision-engineered bobbins. This setup allows for controlled radial expansion under high heat, minimizing distortion and coning. The result? More even pad wear, a firmer pedal feel, and longer component life, even during extended lapping sessions or endurance racing. Floating hardware includes anti-knockback spring clips that reduce piston retraction while eliminating common NVH issues like rattling.
Why Choose AP Racing J Hook Rotors? Advanced Cooling, Superior Bite, Unmatched Durability
At the heart of every rotor is AP Racing’s proprietary high-carbon iron alloy, developed to withstand repeated thermal cycling without cracking or warping. Internally, directional vanes—far superior to OEM pillar or straight vane designs—maximize airflow and cooling. With 60 to 84 vanes per rotor, AP Racing achieves faster heat evacuation, reduced brake fade, and a more consistent friction surface. These rotors are left/right-specific for optimal airflow and balance.
The exclusive J Hook slot pattern offers enhanced initial bite and promotes uniform heat distribution across the rotor face, reducing pad deposits and vibration. Unlike drilled rotors or straight-slot competitors, the J Hook design provides cleaner pad transfer during bed-in and superior modulation under braking—ideal for serious drivers who demand feedback and control. Yes, you might hear a little more whirr, but you’ll gain the stopping power, consistency, and longevity your lap times demand.
Premium Components, Affordable Performance
The rotor hats are CNC-machined from 6061-T6 billet aluminum and hard anodized for strength and heat resistance. Scalloped edges under the hat further assist heat dissipation. All hardware is U.S.-made to AP Racing spec, the same quality found on pro-level racing platforms.
And while these rotors are race-proven, they’re also surprisingly cost-effective to replace. Don’t settle for cheap rotors that crack after a weekend—AP’s J Hook rings offer better durability and real long-term value. Fewer replacements mean more track time, less downtime, and peace of mind knowing you're running the best.
Used by Champions. Trusted by Experts.
From endurance racers to HPDE enthusiasts, AP Racing brake rotors are trusted worldwide for their reliability, longevity, and performance under pressure. Whether you're shaving seconds off your lap time or building a dedicated track car, the J Hook delivers a professional-grade solution that won’t let you down.
AP Racing J Hook Brake Rotors for Auto Racing, Track Days & HPDE
Why Rotor Design Matters: Heat Expansion and Floating Technology
As with most metals, iron brake discs expand significantly under heat. When temperatures rise, the disc grows radially—expanding in both diameter and circumference. Traditional one-piece rotors struggle to accommodate this natural expansion. As the outer edge pulls away from the center under heat stress, it creates a condition called “coning”—a distortion that compromises pad-to-rotor contact. This distortion can lead to uneven pad wear, brake tapering, and an inconsistent, long brake pedal.
AP Racing two-piece floating brake rotors are purpose-built to eliminate these issues. Engineered with “float” built into the disc or hat assembly, these rotors feature oblong-shaped mounting holes that allow the hardware to slide as the disc heats up. This flexibility ensures the disc runs true within the caliper under high-temperature loads, effectively reducing distortion, minimizing pad taper and stress cracks, and promoting longer component life.
Custom Mounting Hardware & Anti-Knockback Spring Clips
AP Racing rotors utilize application-specific, U.S.-made mounting hardware—not generic bolts. These premium components are the exact parts used in AP’s professional motorsport products, engineered to withstand the rigors of competitive racing.
To manage lateral disc motion that can push caliper pistons backward (known as knockback), AP Racing integrates anti-knockback spring clips on alternating bobbins—five on a ten-bolt setup, six on a twelve-bolt disc. These clips keep the aluminum hat and iron disc ring properly aligned while still allowing for radial float. Bonus: they eliminate annoying rattles and vibrations, ensuring a quieter, more refined braking experience.
High-Performance Hat Design for Heat Isolation
The disc hats in AP Racing’s two-piece floating rotors are CNC-machined from 6061-T6 billet aluminum and finished with a hard anodized coating. This high-strength aluminum alloy was selected for its ability to maintain structural integrity even at elevated temperatures. AP adds scalloped channels beneath the hat to further encourage airflow and heat evacuation from the outer disc face, minimizing thermal transfer to hubs and wheel bearings—helping reduce maintenance costs on these expensive components.
Internal Vane Engineering: Airflow Optimization & Thermal Stability
AP Racing’s internal vane design sets them apart from OEM and most aftermarket competitors. While many factory brake discs use non-directional pillar vanes (low-cost and NVH-focused), AP Racing rotors use directional vanes engineered for maximum airflow. These rotors are side-specific—meaning you’ll receive a unique left and right disc in each set—ensuring optimized cooling through strategic vane orientation and shape.
Beyond that, AP Racing rotors feature a superior vane count, typically ranging from 60 to 84 vanes, compared to 30–48 in most aftermarket rotors. After extensive CFD and thermal analysis, this high vane count was proven to:
Increase airspeed and thermal transfer
Reduce recirculation and deflection at the disc face
Minimize coning, cracking, and brake fade
Deliver more even pad contact and extended rotor life
J Hook Slot Pattern: Exclusive to AP Racing
Slots and drill holes may improve initial bite, but they also introduce “cool spots” in the rotor face—areas of uneven heating that can lead to stress risers, cracks, and pad vibration. OEM rotors often avoid this by leaving the disc face blank, but that compromises bite and brake feel.
AP Racing’s patented J Hook design, developed through rigorous R&D, solves this problem. The hooks are meticulously spaced around the disc’s circumference and from hat to edge, forming a continuous distortion path that ensures even heat distribution. This encourages uniform pad deposits during bed-in, helps reduce judder and cracking, and improves consistency under repeated high-load braking.
In addition, the J Hook slots provide more leading edges for pads to grip than traditional curved slots or blank rotors. While this might generate a mild whirring sound during braking, the benefits—more bite, cleaner bedding, better pedal feel—make it the top choice for committed racers and serious track day drivers.
Metallurgy Backed by 50+ Years of Motorsport Leadership
AP Racing's reputation is built on performance, and their proprietary iron alloy used in J Hook rotors is no exception. Drawing from over five decades of elite motorsport experience, including 750+ Formula 1 wins and widespread use across NASCAR, AP’s engineers have developed a disc alloy that excels under sustained racing temperatures and stress. Where OEM discs focus on affordability and mass production, AP Racing’s J Hook rotors are purpose-built for motorsport durability and heat resistance.
Affordable Replacement Cost: Serious Value for Serious Drivers
Even the best brake rotors are consumables. When you drive hard—especially at the track—your discs will eventually wear out. That’s why AP Racing designed their replacement iron rings to be cost-effective, allowing you to replace worn parts without breaking the bank.
Compare that to constantly buying cheap $150 rotors every weekend—rotors that can't handle the heat and need to be swapped frequently. With AP Racing’s J Hook rotors, you get longer service intervals, less downtime, and better performance over time, making them an incredibly smart long-term investment.
Proven on Track. Trusted by Champions.
Top-tier racing teams rely on AP Racing J Hook rotors for one reason: they perform under pressure. Whether you're running time trials, attending HPDE events, or competing in wheel-to-wheel racing, these rotors offer professional-grade reliability, safety, and performance.
Bedding and preparation of AP Racing J Hook Disc
Properly preparing your new brake discs before heavy use is extremely important. The goal of bedding-in your brake pads and discs is to mate them together properly and prepare them for heavy use. When prepared properly, or bed-in, your pads will transfer a thin layer of material to the disc face (transfer layer). The pads in your caliper will then actually ride on that thin layer of pad material you’ve put down on the rotor, rather than rubbing directly on the iron rotor face. A good transfer layer is going to give you superior brake pedal feel, less noise, superior pad wear, and lower the chances of cracking your discs.
Important Notes- PLEASE READ! First, make sure you are on a closed course to perform a proper bed-in. Do NOT perform the procedure on public roads. You need a stretch of asphalt with long straights, good visibility, and no potential obstructions. Make sure you are in a position to safely and repeatedly attain the necessary speeds to perform the bed-in procedure. A controlled racetrack is the best place to perform this procedure. AP Racing and Competition Motorsport in no way suggest or condone speeding on public roads or breaking the law in your car, nor do we take responsibility for any damage or injury that occurs as a result of using our product or these procedures. You are performing the bed-in procedure at your own risk.
During these procedures, it’s critical that you never come to a complete stop with your foot on the brake pedal. If you have brake ducts on your car, you may want to block them off to allow your brake system to heat up easily. The procedure outlined below is a generic procedure for most types of mild race pad. Please check your pad manufacturer’s recommended bed-in procedure.
Accelerate to approximately 60mph and then decelerate down to 5 mph. If your car has ABS, you should try to hold the brakes at a point just before ABS intervention.
Once the car slows to 5mph, immediately accelerate back up to about 60mph, and brake again to roughly 5mph.
Repeat this series of stopping and accelerating 8 to 10 times. Again, do not come to a complete stop with your foot on the brake pedal.
Cool the brake system down by cruising at 45mph+ for 5 to 10 minutes.
Visually inspect your discs. They should be a blue/grey color (instead of shiny silver), and have an even layer of pad material across and around the entire rotor face.
If the AP Racing rotors don’t have a layer of pad material on them, perform another series of stops in the manner outlined above.

AP Racing
AP Racing 408x34mm 2-piece J Hook Front Brake Rotors - Porsche 992 GT3, GT3 RS Iron & PCCB
$2,499.00
AP Racing by Essex 2-piece "S" Vane J Hook Front Brake Rotors (Front 408 x 34mm)- Porsche 992 GT3, GT3 RS Iron & PCCB
Fit The Following Cars (w/ OEM Iron Rotors or PCCB Rotors)
Porsche 992 GT3 (Front)
Porsche 992 GT3RS (Front)
Sold/priced per pair.
AP Racing 2-piece S Vane Competition J Hook front disc pair for 992 GT3 and GT3 RS with iron or PCCB discs.
***Note for PCCB cars - must be used with the smaller D62 iron disc pad shape (Ferodo FCP4664 - DS3.12 / DS1.11)
Massive increase in airflow, cooling capacity, and durability vs. OEM discs or even conventional curved vane discs
408mm x 34mm (16.06" x 1.34") , 84 Sinusoidal "wave" vanes, D62 radial depth
Designed for: club racing, time trial, autocross, HPDE
Works with OEM calipers, no modifications required
Ultralight, fully floating, anodized billet aluminum hat with float control/anti-rattle clips
We are introducing a new internal vane technology in our front 2-piece discs for the 992 GT3. It is called the Sinusoidal Vane, which AP sometimes refers to internally as the 'Wave' Vane for obvious reasons as you’ll see below. This tech is something that has helped AP Racing brake systems win championships in international GT racing, as well as multiple NASCAR Cup championships here in North America. As one of the most desirable track weapons on the planet, we wanted the 992 GT3 to be the first production car application for this technology in North America. Just as AP Racing's Radi-CAL calipers set a new benchmark for caliper stability, cooling, and durability, the Sinusoidal Vanes have done the same for iron racing discs.
The concept for this disc design originated in NASCAR Cup. Up until the debut of the Next Gen car (for which AP/Essex are supplying the spec brake package), we were cramming our brake systems inside tiny 15” wheels. Trying to squeeze adequate brake thermal mass into a wheel that small is incredibly challenging, particularly when you have a 1,000 HP and 3,000 pounds mashing on them every few seconds from 200 mph…for hours on end! In a wheel that small, there isn’t anywhere for the heat to go, and the durability of every component is crucial. We were constantly looking for ways to provide the Cup teams with increased durability, stability, and cooling, and that’s what led AP to this technology.
Benefits of the Wave Vane disc technology vs. traditional curved vanes:
Increased thermal stability- Wild temperature swings are what causes discs to crack. When you stand on the brakes for an approaching corner, your disc temperatures skyrocket and the iron expands. As you travel down the subsequent straight, the discs are blasted with cooling air. The longer the straight and the higher the speed, the greater the temperature drop, and the further the iron contracts. This expansion and contraction cycle places a huge amount of stress on the iron and is what causes them to eventually crack. That’s why tracks with relatively slow corners at the end of high-speed straights, followed by another long straight, decimate brake discs (think Watkins Glen or Road America). In an ideal world, once you brought your discs up to race temps, you would keep them at a constant temperature for the entire session. The Sinusoidal Vane brings the discs closer to that goal by decreasing the difference between the maximum and minimum disc temperature by as much as 35%. That means a less dramatic temperature swing and greater crack resistance and durability.
Reduced maximum disc temperatures by 10%+: Not only are temperature swings less intense with the Wave Vane, the maximum temperatures reached are substantially lower. For example, in one NASCAR test the Wave Vane discs showed a peak temp of 1328F and a minimum temp of 1085F (delta of 243F), while the traditional curved vanes maxed out at 1490F and a min of 1121F (delta of 369F). Not only was the difference between min and max more subdued, the max temperature reached by the Wave Vane disc was 162F lower!
Increased cooling surface area- Each of the internal Wave Vanes has a larger cooling surface area vs. a traditional curved vane.
Greater support for the disc face- A disc’s internal vane structure provides the support lattice behind the disc face. Having many internal vanes impacts airspeed and heat transfer through the disc, reduces air recirculation between vanes, and reduces deflection at the disc face. In practical terms, a disc with a high number of vanes is more thermally stable, maintains more even contact with the brake pads (which reduces uneven pad deposits/judder), and is less prone to distortion. In summary, the Wave Vane design provides even greater support for the disc face than AP’s standard curved vane designs.
Reduced weight- The Wave Vane design provides a slight unsprung weight reduction vs. a similar disc with curved internal vanes.
AP Racing J Hook Brake Rotors – The Gold Standard in Track Day & Racing Performance
Engineered for professional motorsport, HPDE, and dedicated track day use, AP Racing’s J Hook Brake Rotors deliver uncompromising performance, thermal stability, and consistent braking power. These two-piece, floating rotors are built to handle the extreme demands of road racing, with design features derived from over 50 years of elite competition—including Formula 1, NASCAR, and IMSA.
Unlike conventional one-piece rotors, AP Racing’s two-piece floating design features a billet aluminum hat mated to a cast iron disc via precision-engineered bobbins. This setup allows for controlled radial expansion under high heat, minimizing distortion and coning. The result? More even pad wear, a firmer pedal feel, and longer component life, even during extended lapping sessions or endurance racing. Floating hardware includes anti-knockback spring clips that reduce piston retraction while eliminating common NVH issues like rattling.
Why Choose AP Racing J Hook Rotors? Advanced Cooling, Superior Bite, Unmatched Durability
At the heart of every rotor is AP Racing’s proprietary high-carbon iron alloy, developed to withstand repeated thermal cycling without cracking or warping. Internally, directional vanes—far superior to OEM pillar or straight vane designs—maximize airflow and cooling. With 60 to 84 vanes per rotor, AP Racing achieves faster heat evacuation, reduced brake fade, and a more consistent friction surface. These rotors are left/right-specific for optimal airflow and balance.
The exclusive J Hook slot pattern offers enhanced initial bite and promotes uniform heat distribution across the rotor face, reducing pad deposits and vibration. Unlike drilled rotors or straight-slot competitors, the J Hook design provides cleaner pad transfer during bed-in and superior modulation under braking—ideal for serious drivers who demand feedback and control. Yes, you might hear a little more whirr, but you’ll gain the stopping power, consistency, and longevity your lap times demand.
Premium Components, Affordable Performance
The rotor hats are CNC-machined from 6061-T6 billet aluminum and hard anodized for strength and heat resistance. Scalloped edges under the hat further assist heat dissipation. All hardware is U.S.-made to AP Racing spec, the same quality found on pro-level racing platforms.
And while these rotors are race-proven, they’re also surprisingly cost-effective to replace. Don’t settle for cheap rotors that crack after a weekend—AP’s J Hook rings offer better durability and real long-term value. Fewer replacements mean more track time, less downtime, and peace of mind knowing you're running the best.
Used by Champions. Trusted by Experts.
From endurance racers to HPDE enthusiasts, AP Racing brake rotors are trusted worldwide for their reliability, longevity, and performance under pressure. Whether you're shaving seconds off your lap time or building a dedicated track car, the J Hook delivers a professional-grade solution that won’t let you down.
AP Racing J Hook Brake Rotors for Auto Racing, Track Days & HPDE
Why Rotor Design Matters: Heat Expansion and Floating Technology
As with most metals, iron brake discs expand significantly under heat. When temperatures rise, the disc grows radially—expanding in both diameter and circumference. Traditional one-piece rotors struggle to accommodate this natural expansion. As the outer edge pulls away from the center under heat stress, it creates a condition called “coning”—a distortion that compromises pad-to-rotor contact. This distortion can lead to uneven pad wear, brake tapering, and an inconsistent, long brake pedal.
AP Racing two-piece floating brake rotors are purpose-built to eliminate these issues. Engineered with “float” built into the disc or hat assembly, these rotors feature oblong-shaped mounting holes that allow the hardware to slide as the disc heats up. This flexibility ensures the disc runs true within the caliper under high-temperature loads, effectively reducing distortion, minimizing pad taper and stress cracks, and promoting longer component life.
Custom Mounting Hardware & Anti-Knockback Spring Clips
AP Racing rotors utilize application-specific, U.S.-made mounting hardware—not generic bolts. These premium components are the exact parts used in AP’s professional motorsport products, engineered to withstand the rigors of competitive racing.
To manage lateral disc motion that can push caliper pistons backward (known as knockback), AP Racing integrates anti-knockback spring clips on alternating bobbins—five on a ten-bolt setup, six on a twelve-bolt disc. These clips keep the aluminum hat and iron disc ring properly aligned while still allowing for radial float. Bonus: they eliminate annoying rattles and vibrations, ensuring a quieter, more refined braking experience.
High-Performance Hat Design for Heat Isolation
The disc hats in AP Racing’s two-piece floating rotors are CNC-machined from 6061-T6 billet aluminum and finished with a hard anodized coating. This high-strength aluminum alloy was selected for its ability to maintain structural integrity even at elevated temperatures. AP adds scalloped channels beneath the hat to further encourage airflow and heat evacuation from the outer disc face, minimizing thermal transfer to hubs and wheel bearings—helping reduce maintenance costs on these expensive components.
J Hook Slot Pattern: Exclusive to AP Racing
Slots and drill holes may improve initial bite, but they also introduce “cool spots” in the rotor face—areas of uneven heating that can lead to stress risers, cracks, and pad vibration. OEM rotors often avoid this by leaving the disc face blank, but that compromises bite and brake feel.
AP Racing’s patented J Hook design, developed through rigorous R&D, solves this problem. The hooks are meticulously spaced around the disc’s circumference and from hat to edge, forming a continuous distortion path that ensures even heat distribution. This encourages uniform pad deposits during bed-in, helps reduce judder and cracking, and improves consistency under repeated high-load braking.
In addition, the J Hook slots provide more leading edges for pads to grip than traditional curved slots or blank rotors. While this might generate a mild whirring sound during braking, the benefits—more bite, cleaner bedding, better pedal feel—make it the top choice for committed racers and serious track day drivers.
Metallurgy Backed by 50+ Years of Motorsport Leadership
AP Racing's reputation is built on performance, and their proprietary iron alloy used in J Hook rotors is no exception. Drawing from over five decades of elite motorsport experience, including 750+ Formula 1 wins and widespread use across NASCAR, AP’s engineers have developed a disc alloy that excels under sustained racing temperatures and stress. Where OEM discs focus on affordability and mass production, AP Racing’s J Hook rotors are purpose-built for motorsport durability and heat resistance.
Affordable Replacement Cost: Serious Value for Serious Drivers
Even the best brake rotors are consumables. When you drive hard—especially at the track—your discs will eventually wear out. That’s why AP Racing designed their replacement iron rings to be cost-effective, allowing you to replace worn parts without breaking the bank.
Compare that to constantly buying cheap $150 rotors every weekend—rotors that can't handle the heat and need to be swapped frequently. With AP Racing’s J Hook rotors, you get longer service intervals, less downtime, and better performance over time, making them an incredibly smart long-term investment.
Proven on Track. Trusted by Champions.
Top-tier racing teams rely on AP Racing J Hook rotors for one reason: they perform under pressure. Whether you're running time trials, attending HPDE events, or competing in wheel-to-wheel racing, these rotors offer professional-grade reliability, safety, and performance.
Bedding and preparation of AP Racing J Hook Disc
Properly preparing your new brake discs before heavy use is extremely important. The goal of bedding-in your brake pads and discs is to mate them together properly and prepare them for heavy use. When prepared properly, or bed-in, your pads will transfer a thin layer of material to the disc face (transfer layer). The pads in your caliper will then actually ride on that thin layer of pad material you’ve put down on the rotor, rather than rubbing directly on the iron rotor face. A good transfer layer is going to give you superior brake pedal feel, less noise, superior pad wear, and lower the chances of cracking your discs.
Important Notes- PLEASE READ! First, make sure you are on a closed course to perform a proper bed-in. Do NOT perform the procedure on public roads. You need a stretch of asphalt with long straights, good visibility, and no potential obstructions. Make sure you are in a position to safely and repeatedly attain the necessary speeds to perform the bed-in procedure. A controlled racetrack is the best place to perform this procedure. AP Racing and Competition Motorsport in no way suggest or condone speeding on public roads or breaking the law in your car, nor do we take responsibility for any damage or injury that occurs as a result of using our product or these procedures. You are performing the bed-in procedure at your own risk.
During these procedures, it’s critical that you never come to a complete stop with your foot on the brake pedal. If you have brake ducts on your car, you may want to block them off to allow your brake system to heat up easily. The procedure outlined below is a generic procedure for most types of mild race pad. Please check your pad manufacturer’s recommended bed-in procedure.
Accelerate to approximately 60mph and then decelerate down to 5 mph. If your car has ABS, you should try to hold the brakes at a point just before ABS intervention.
Once the car slows to 5mph, immediately accelerate back up to about 60mph, and brake again to roughly 5mph.
Repeat this series of stopping and accelerating 8 to 10 times. Again, do not come to a complete stop with your foot on the brake pedal.
Cool the brake system down by cruising at 45mph+ for 5 to 10 minutes.
Visually inspect your discs. They should be a blue/grey color (instead of shiny silver), and have an even layer of pad material across and around the entire rotor face.
If the AP Racing rotors don’t have a layer of pad material on them, perform another series of stops in the manner outlined above.

AP Racing
AP Racing Radi-CAL R3 Racing Brake Fluid (500 ml)
$29.95
AP Racing Radi-CAL R3 Racing Brake Fluid
Designed for the Top Levels of Motorsports
AP Radi-CAL R3 Racing Brake Fluid was developed for use in very-high-temperature racing conditions. It conforms to or exceeds FMVSS 116, DOT 4, SAE J1703 and J1704 standards. AP Racing Radi-CAL R3 Racing Brake Fluid is one of the most popular brake fluids at the highest levels of professional auto and motorcycle racing. It was specifically developed for coping with extraordinary temperatures, such as those encountered when running a carbon/carbon composite brake system.
To ensure that the fluid stays fresh, AP brake fluids are furnished in 500 ml (16.9 oz) easy-pour plastic bottles with double-sealed caps. When switching your fluid to AP Racing Radi-CAL R3, we recommend purging all of the old fluid from the system. Three to four bottles of fluid are enough to completely replace existing brake fluid and still have enough left over for a bleed at the track to remove any remaining air bubbles.
AP Racing Radi-CAL R3 Brake Fluid Details:
Manufacturer: AP Racing
Manufacturer part number: AP-CP5660
UPC: 48238040081
DOT Rating: DOT 4
Dry Boiling Point: 617º F / 325º C
Wet Boiling Point: 383º F / 195º C
Compatible with other DOT 4 fluids: yes
Bottle size: 500 ml (16.9 fl oz)