AP Racing Radi-Cal 390mm Competition Brake Kit for Porsche (Front) Fit The Following Cars Porsche 991 Carrera S/4S/GTS (PCCB and Iron Rotors) Porsche 992 Carrera base and Carrera 4 (Iron Rotors) Complete front AP Racing Radi-Cal Competition Brake Kit for Porsche 991 911 S/4S/GTS and 992 Carrera base and Carrera 4. Features AP Racing Radi-Cal 9669 calipers with option for 25mm (1 inch) thick pads for extreme durability! Jewel-like ENP Caliper finish is incredibly durable and easy to clean 390x36mm iron discs are resilient under heavy track use, and replacements cost one tenth of PCCB ($600 vs. $6,000 per disc) Shaves over 20 lbs. off the front axle vs oem iron brakes Only adds approximately one pound per side of unsprung weight vs. the OEM PCCB setup Fits inside 19" wheels, which the OEM PCCB discs cannot do, allowing for additional unsprung weight reduction plus improved tire options Our AP Racing Radi-Cals feature a removable bridge, making pad swaps far faster and easier than stock calipers Commonly available AP Racing pad shapes provide a wide selection of brake pad choices to tailor system feel and performance Removing the stock calipers and PCCB discs allows them to be preserved undamaged, retaining the vehicle's future resale value AP systems typically trade hands on the used market at 65% or more of their original MSRP, lowering the long-term cost of ownership. Use them for a few years and recoup a large portion of your initial investment. Designed to work with our matching 365mm Radi-Cal brake kit.

AP Racing Radi-Cal 372mm Competition Brake Kit for Porsche (Front) Fit The Following Cars Porsche 991 Carrera S/4S/GTS (PCCB and Iron Rotors) Porsche 992 Carrera base / Carrera 4 (Iron Rotors) Complete front AP Racing Radi-Cal Competition Brake Kit for Porsche features; Features AP Racing Radi-Cal 9669 calipers with option for 25mm (1 inch) thick pads for extreme durability! Jewel-like ENP Caliper finish is incredibly durable and easy to clean 372x34mm iron discs are resilient under heavy track use, and replacements cost one tenth of PCCB ($600 vs. $6,000 per disc) Shaves over 20 lbs. off the front axle vs oem iron brakes Only adds approximately one pound per side of unsprung weight vs. the OEM PCCB setup Fits inside 19" wheels, which the OEM PCCB discs cannot do, allowing for additional unsprung weight reduction plus improved tire options Our AP Racing Radi-Cals feature a removable bridge, making pad swaps far faster and easier than stock calipers Commonly available AP Racing pad shapes provide a wide selection of brake pad choices to tailor system feel and performance Removing the stock calipers and PCCB discs allows them to be preserved undamaged, retaining the vehicle's future resale value AP systems typically trade hands on the used market at 65% or more of their original MSRP, lowering the long-term cost of ownership. Use them for a few years and recoup a large portion of your initial investment. Designed to work with our matching 365mm Radi-Cal brake kit.

AP Racing Road 380mm Road Brake Kit for Porsche (Front) Fit The Following Cars Porsche 991 Carrera S/4S/GTS (PCCB and Iron Rotors) Porsche 992 Carrera Base / Carrera 4 (PCCB and Iron Rotors) Complete front AP Racing Road Brake Kit for Porsche 991 and 992 911 features; Features AP Racing Radi-Cal 9562 calipers. Available with Black, Red, or Silver Calipers Takes your brakes into GT3 territory with huge 380x36mm, 72 vane AP Racing J Hook discs Painted calipers with dust boots add durability in inclement weather conditions Low noise, vibration, and harshness for a very OE-like experience during daily driving Leverages six piston AP Racing CP9562 World Radi-CAL II calipers with a red, black, or silver painted finish Utilizes large volume brake pads for heat absorption and longevity Pistons sized properly to maintain proper brake bias and work with the OEM master cylinder and ABS system Designed to mate with OEM rear brakes or our matching rear AP Racing Road Brake Kit

AP Racing Radi-Cal 365mm Competition Brake Kit for Porsche (Rear) Fit The Following Cars Porsche 991 Carrera S/4S/GTS (PCCB and Iron Rotors) Complete front AP Racing Radi-Cal Competition Brake Kit for Porsche 991 911 S/4S/GTS features; Features AP Racing Radi-Cal 9449 calipers  Jewel-like ENP Caliper finish is incredibly durable and easy to clean 365x30mm iron discs are resilient under heavy track use, and replacements cost one tenth of PCCB ($600 vs. $6,000 per disc) Shaves up to  9lbs. off the rear axle vs oem iron brakes Only adds approximately one pound per side of unsprung weight vs. the OEM PCCB setup Fits inside 19" wheels, which the OEM PCCB discs cannot do, allowing for additional unsprung weight reduction plus improved tire options Our AP Racing Radi-Cals feature a removable bridge, making pad swaps far faster and easier than stock calipers Commonly available AP Racing pad shapes provide a wide selection of brake pad choices to tailor system feel and performance Removing the stock calipers and PCCB discs allows them to be preserved undamaged, retaining the vehicle's future resale value AP systems typically trade hands on the used market at 65% or more of their original MSRP, lowering the long-term cost of ownership. Use them for a few years and recoup a large portion of your initial investment. Designed to work with our matching Front Radi-Cal brake kit.

AP Racing Road 380mm Road Brake Kit for Porsche (Rear) Fit The Following Cars Porsche 991 Carrera S/4S/GTS (PCCB and Iron Rotors) Porsche 992 Carrera / Carrera 4 (PCCB and Iron Rotors) Complete front AP Racing Road Brake Kit for Porsche 991 and 992 911 features; Takes your brakes into GT3 territory with huge 380x28mm, 48 vane AP Racing J Hook discs Retains full function of OEM parking brake Painted calipers with dust boots add durability in inclement weather conditions Low noise, vibration, and harshness for a very OE-like experience during daily driving Leverages four piston AP Racing CP9541 World Radi-CAL II calipers with a red, black, or silver painted finish Pistons sized properly to maintain proper brake bias and work with the OEM master cylinder and ABS system Designed to mate with the front AP Racing Road Brake kit Weighs roughly the same as an OEM rear rear brake setup despite a huge size increase of the rotor size to 380mm

Brembo 2-Piece Slotted Rotors Porsche 991.1 Carrera S/4S/GTS (Rear) 350x26mm (13.8") 2-Piece disc complete axle set.  Pre-Assembled with all necessary hardware Included Track-Ready Performance, Street-Driven Reliability Upgrade your braking system with the Brembo Type 3 2-Piece Floating Rotors, precision-engineered for the Porsche 991.1 Carrera S, Carrera 4S, and GTS models equipped with standard iron brakes (non-PCCB). Designed for high-performance street driving, autocross, and track-day use, these rotors deliver enhanced thermal management, reduced unsprung weight, and longer pad life. Each rotor features a lightweight billet aluminum hat mated to a directionally slotted, heat-treated iron outer ring, optimizing brake cooling and rotor stability under extreme conditions. The floating design reduces stress transfer to the hub, helping to minimize cracking, coning, and distortion during repeated high-speed stops. With OE-matched dimensions, these rotors offer direct bolt-on fitment with no modifications required. Whether you're shaving seconds on the track or just want more confidence on the road, the Brembo 2-piece rotor set is the perfect upgrade to unleash the full potential of your 991.1 Carrera S, 4S, or GTS. Backed by competition-proven engineering and trusted by performance enthusiasts nationwide, this is the brake rotor solution serious drivers choose. Fits: 2012-2016 Porsche 991 Carrera S / 4S / GTS (excludes PCCB models) Lightweight 2-piece floating design with aluminum center hat Slotted surface for enhanced cooling and pad bite Reduces unsprung mass and improves rotor longevity Direct OEM replacement — no modification needed Track-tested for performance and durability Competition Motorsport is an Authorized dealer for Brembo products and we are one of the largest stocking dealers in the country.   The Brembo two piece rotor system is a direct rotor disc replacement for the oem hat and rotor  and is designed to be used with oem calipers with no modifications necessary.   The 2-piece Brembo design allows for rotor only replacement to minimize replacement costs and deliver outstanding performance and cooling.

Brembo 2-Piece Slotted Rotors Porsche 991 Carrera S/4S/GTS (Front) 350x34mm (13.8") 2-Piece disc complete axle set.  Pre-Assembled with all necessary hardware Included Track-Ready Performance, Street-Driven Reliability Upgrade your braking system with the Brembo Type 3 2-Piece Floating Rotors, precision-engineered for the Porsche 991 Carrera S, Carrera 4S, and GTS models equipped with standard iron brakes (non-PCCB). Designed for high-performance street driving, autocross, and track-day use, these rotors deliver enhanced thermal management, reduced unsprung weight, and longer pad life. Each rotor features a lightweight billet aluminum hat mated to a directionally slotted, heat-treated iron outer ring, optimizing brake cooling and rotor stability under extreme conditions. The floating design reduces stress transfer to the hub, helping to minimize cracking, coning, and distortion during repeated high-speed stops. With OE-matched dimensions, these rotors offer direct bolt-on fitment with no modifications required. Whether you're shaving seconds on the track or just want more confidence on the road, the Brembo 2-piece rotor set is the perfect upgrade to unleash the full potential of your 991 Carrera S, 4S, or GTS. Backed by competition-proven engineering and trusted by performance enthusiasts nationwide, this is the brake rotor solution serious drivers choose. Fits: 2012-2019 Porsche 991 Carrera S / 4S / GTS (excludes PCCB models) Lightweight 2-piece floating design with aluminum center hat Slotted surface for enhanced cooling and pad bite Reduces unsprung mass and improves rotor longevity Direct OEM replacement — no modification needed Track-tested for performance and durability Competition Motorsport is an Authorized dealer for Brembo products and we are one of the largest stocking dealers in the country.   The Brembo two piece rotor system is a direct rotor disc replacement for the oem hat and rotor  and is designed to be used with oem calipers with no modifications necessary.   The 2-piece Brembo design allows for rotor only replacement to minimize replacement costs and deliver outstanding performance and cooling.

AP Racing 350x30mm 2-piece J Hook Rear Floating Racing Brake Rotors Fit The Following Cars (w/ OEM Iron Rotors) Porsche 991 911 S/4S/GTS  Porsche 997 911 S/4S/GTS Porsche 996 911 GT3 AP Racing 2-piece Competition J Hook front disc pair for  with iron discs 350mm x 30mm (13.78" x 1.18") 72 Vane, D66 Huge increase in airflow, cooling capacity, and durability vs. OEM discs Saves 2 lbs. unsprung weight per side vs. OEM iron discs 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 350x34mm 2-piece J Hook Front Floating Racing Brake Rotors Fit The Following Cars (w/ OEM Iron Rotors) Porsche 991 S/4S/GTS (Front) Porsche 992 S/4S/GTS (Front) AP Racing 2-piece Competition J Hook front disc pair for  with iron discs 350mm x 34mm (13.78" x 1.34") 72 Vane, D66 Huge increase in airflow, cooling capacity, and durability vs. OEM discs Saves 2 lbs. unsprung weight per side vs. OEM iron discs 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.

Girodisc Porsche 996 / 991 / 992 Rear Rotors (with Spacers & Bolts) The Girodisc A2-032B Rear Rotor Kit is a premium direct-fit replacement for Porsche 996, 991, and 992 models. Engineered for high-performance driving, this system includes caliper spacers and longer bolts to accommodate the larger 350mm rotors. The result is improved braking torque, enhanced cooling efficiency, and reduced unsprung mass—all while retaining factory fitment and ABS calibration. Lightweight Design & Increased Performance Each Girodisc rotor assembly pairs a CNC-machined 6061-T6 aluminum hat with a proprietary cast iron disc. The 2-piece design significantly reduces rotational mass compared to OEM rotors, improving suspension response and acceleration. The curved vane design acts as a centrifugal pump, drawing air through the rotor to enhance cooling and resist fade under extreme braking conditions. Precision Floating Mount System The rotors feature Girodisc’s race-proven floating mount design with 10 cadmium-plated steel drive pins connecting the iron ring to the aluminum hat. These pins allow the disc to expand radially under high temperatures without warping, ensuring consistent pad contact. Anti-noise spring washers eliminate rattle, maintaining quiet operation suitable for street and track use alike. Vehicle Fitment Porsche 996 Carrera / Carrera 4 / Carrera 4S Porsche 991 Carrera / Carrera 4 / Carrera GTS (Base models require S/4S/GTS rear pad shape for full rotor sweep) Porsche 992 Carrera / Carrera S / Carrera 4S Direct bolt-on installation with supplied spacers and hardware Technical Specifications CMS Number: A2-032B Position: Rear Rotor Diameter: 350mm (includes caliper spacers & longer bolts) Design: 2-piece floating rotor assembly Material: Proprietary cast iron with 6061-T6 aluminum hat Vane Design: Curved directional vanes for improved airflow Hardware: Cadmium-plated steel drive pins, class 12.9 screws, anti-noise washers Rebuildable: Yes — replace rotor rings, reuse aluminum hats Sold/Price: Per pair Girodisc A2-032B FAQs Do these rotors fit all Porsche 996, 991, and 992 models? Yes. However, 991 base Carrera models must use the S/4S/GTS rear pad shape for full pad sweep. What is included with this kit? Each kit includes two 350mm rotors, caliper spacers, and longer mounting bolts for a complete direct installation. Are modifications required? No. The supplied hardware makes this a true bolt-on upgrade using factory calipers and lines. What are the main benefits over stock rotors? Improved cooling, reduced weight, better pedal response, and replaceable rings for long-term cost savings. Upgrade your Porsche’s braking system with the Girodisc A2-032B Rear Rotor Kit. Experience reduced fade, sharper braking response, and long-term durability whether on the street or at the track.

Porsche 991.1 S, 4S, GTS Front Rotors The Girodisc 2-piece floating rotor system is a direct replacement for the factory rotors on the Porsche 991.1 Carrera S, 4S, and GTS. This upgrade includes precision caliper spacers that allow the installation of larger 350 mm rotors in place of the factory 340 mm discs, resulting in increased braking torque, improved cooling, and reduced fade under demanding conditions. The Girodisc rotors weigh approximately 21.0 lbs each, compared to the 24.4 lbs OEM units—reducing rotational mass for sharper acceleration and suspension response. Each rotor features a CNC-machined 6061-T6 aluminum hat bolted to Girodisc’s proprietary high-carbon cast-iron rings. The internal curved vane design functions as a centrifugal air pump, pulling cool air through the disc to efficiently dissipate heat during high-performance driving. Engineered and manufactured entirely in the USA, Girodisc rotors deliver exceptional braking consistency and reliability on both street and track. Precision-Engineered Performance Vehicle Fitment Porsche 991.1 Carrera S Porsche 991.1 Carrera 4S Porsche 991.1 Carrera GTS Features Direct replacement with included spacers: Increases rotor size to 350 mm for enhanced braking force and heat management. Lightweight construction: 21.0 lbs per rotor versus 24.4 lbs OEM reduces unsprung and rotational weight. Curved vane design: Actively circulates air through the rotor for superior cooling and fade resistance. Floating mount system: Cadmium-plated steel drive pins and anti-noise spring washers manage thermal expansion while eliminating rattle. Serviceable two-piece design: Replace only the iron rings when worn for reduced long-term cost. Made in the USA: Cast, machined, and assembled entirely in-house for unmatched quality control. FAQs Will these work with OEM calipers? Yes. Girodisc rotors are designed to work perfectly with stock calipers and come with spacers for proper fitment. Do I need to change brake pads? No. You can continue using your current OEM or aftermarket pads. Are these suitable for track use? Yes. The curved vane design and floating assembly ensure consistent braking under extreme temperatures. Do they affect ABS or brake balance? No. Factory brake bias and ABS functionality remain unchanged. How are they sold? Sold and priced per pair. Upgrade your 991.1 Carrera with Girodisc’s 350 mm floating rotors for improved cooling, reduced fade, and sharper pedal feel—engineered for performance driving enthusiasts.

Girodisc Porsche 350mm Rear Rotors Upgrade the braking performance of your Porsche 997 Turbo with Girodisc’s lightweight 350mm rear rotors. Designed for both PCCB and non-PCCB vehicles, these direct-fit rotors reduce unsprung mass, improve cooling efficiency, and provide consistent braking power on road or track. Vehicle Fitment Porsche 997 Turbo (All Models)Works with PCCB and non-PCCB brake systemsDirect OEM replacement – bolts to factory calipers and hardware Built for Precision and Performance The Girodisc system replaces the OEM rotor with a two-piece floating assembly that combines a CNC-machined 6061-T6 aluminum hat and a proprietary cast-iron friction ring, both produced in the USA. The curved vane internal design functions as a centrifugal pump, drawing air through the rotor to keep temperatures stable under heavy braking. This setup maintains factory brake bias and ABS calibration while delivering quicker cooling and improved pedal feel. Features • Direct OEM replacement – no modifications required• 6061-T6 billet aluminum hats, anodized for durability• Proprietary cast-iron friction rings cast and machined in the USA• Floating mount system with cadmium-plated steel drive pins• Anti-noise spring washers prevent rattle while allowing thermal expansion• Curved internal vane design improves cooling and fade resistance• Reduces unsprung and rotational mass• Maintains OEM brake bias and ABS function• Fully rebuildable – replace only friction rings when worn• Sold/priced per pair Girodisc A2-032 Rear Rotor FAQs: Will these work on both PCCB and steel-rotor cars? Yes. They’re engineered to fit either configuration of the 997 Turbo without modification, using your factory calipers and hardware. How do they compare to the factory PCCB rotors? Girodisc rotors offer improved heat tolerance and lower long-term costs, with performance closer to a motorsport-grade iron system while retaining OEM compatibility. What benefits will I notice on track? Expect better heat management, reduced fade, and more consistent pedal feel—even during repeated high-speed braking sessions. Are they serviceable? Absolutely. When the friction rings wear out, they can be replaced separately, making these rotors a long-term performance investment. Enhance your Porsche 997 Turbo’s braking confidence with Girodisc 350mm rear rotors—engineered for precision, performance, and endurance.

A1-122 Girodisc Two-Piece 350mm Front Brake Rotors (Discontinued Design) FITMENT: Porsche Carrera S 991.2 Porsche Carrera 4S 991.2 Porsche Carrera GTS 991.2 Discontinued New old stock rotor.  These have the straight grooves as images show, not the new curved grooves.  Final Sale, no returns or exchanges. This Girodisc system is a direct replacement for OEM Porsche steel (cast iron) rotors1 with the use of the provided caliper spacers. The Girodisc rotors are slightly larger than the stock Porsche rotors at 350mm vs. 340mm, providing greater braking force and cooling capacity. The Girodisc front rotors are approximately 21.0 lbs. vs. 24.4 lbs. for the stock units. This reduction in rotational and unsprung weight allows for quicker acceleration and suspension response. The central hat section of the disc is made from 6061-T6 aircraft specification aluminum. The disc is manufactured from cast iron constructed in the USA, made to the same specification with the same material used by professional racing organizations. The rotors' curved vane design was developed in racing and acts as a centrifugal pump to force cooling air through the disc. The rotor and hat mount together through a floating mount system which utilizes ten high strength alloy steel drive pins manufactured by Girodisc in the USA to their own specifications and are cadmium plated for corrosion resistance. The alloy drive pins transfer the load from the brake action while maintaining the axial and radial float between the disc rotor and hat. The pins are secured by Grade-12 cap screws with hardened washers and mounted with anti-noise spring washers to allow for heat expansion while eliminating the rattle and noise associated with floating rotors. The two-piece Girodisc design allows for disc-only replacement as well, minimizing future replacement costs and delivering outstanding performance. Sold/priced per pair. 1 Note: this Girodisc kit does not fit Porsche models with factory PCCB brakes.

AP Racing J Hook 350x28mm 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 13.01.20014. Fits The Following Cars (w/ OEM iron rotors): Porsche 992 911 S/4S/GTS Porsche 991 911 S/4S/GTS 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 J Hook 350x34mm Replacement Front 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 13.01.20012. Fits The Following Cars (w/ OEM iron rotors): Porsche 992 911 S/4S/GTS Porsche 991 911 S/4S/GTS 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.

D1-122 Girodisc Porsche Front Rings Maintain your Porsche’s precision braking feel with Girodisc D1-122 340mm front replacement rings. Designed to bolt directly to your existing Girodisc aluminum hats using the included floating hardware kit, these rings provide OEM fitment with track-proven performance. Each rotor ring is CNC-machined from Girodisc’s proprietary high-carbon cast iron, offering exceptional heat management, reduced unsprung weight, and improved consistency under demanding driving conditions. Vehicle Fitment Compatible with:• Porsche 991.1 Carrera S (2012–2016)• Porsche 991.1 Carrera 4S (2012–2016)• Porsche 991.1 Carrera GTS (2014–2016)Note: Designed exclusively for Girodisc 340mm two-piece front rotor systems. Not compatible with OEM one-piece or PCCB carbon-ceramic rotors. Features • Sold as a left/right pair with complete floating hardware kit• Direct replacements for Girodisc 340mm two-piece front rotors• High-carbon iron alloy ensures stable friction and long-term durability• Directional curved vanes optimize cooling airflow and reduce rotor temperatures• Maintains factory brake bias, ABS, and stability control calibration• Precision-balanced to eliminate vibration and ensure smooth braking• Designed exclusively for Girodisc aluminum hats Specifications • Diameter: 340 mm• Position: Front• Material: High-carbon cast iron• Mount type: Floating two-piece system• Includes: Two rotor rings and complete hardware kit• Sold/priced per pair Girodisc D1-122 Porsche Front Replacement Ring FAQs Can these be used with OEM Porsche rotor hats? No. These rings are engineered specifically for Girodisc aluminum hats and will not fit OEM one-piece or PCCB systems. Which brake pad compounds are recommended? For street and occasional track driving, Pagid RS29 or Ferodo DS2500 pads are excellent choices. For full track use, use higher-friction compounds such as Pagid RSL1. What torque specification is required for the hardware? Torque each bolt to 12 ft-lbs (16 Nm) with blue Loctite, then recheck after one full heat cycle for proper seating. Are these rotors directional? Yes. Each rotor is marked for left or right installation to ensure proper airflow through the curved internal vanes, maximizing cooling efficiency. Upgrade your Porsche 991.1 Carrera’s braking performance with Girodisc D1-122 340mm front replacement rings — designed for heat control, balance, and endurance from road to track.