Girodisc Porsche 390mm Rear Rotor Rings
The Girodisc D2-154 Rear Replacement Rotor Rings are precision-engineered replacements for Girodisc two-piece rear rotors on Porsche GT models. Designed to restore the braking performance, cooling capacity, and balance of your Girodisc system, these rings deliver exceptional quality and durability for both street and track use.
Vehicle Fitment
• Porsche 991 GT3 / GT3 RS – Rear
• Porsche 992 GT3 / GT3 RS – Rear
• Porsche 718 GT4 RS – Rear
• Designed for Girodisc two-piece rotor systems
• Will not fit OEM or non-Girodisc two-piece rotors
Track-Proven Engineering for Porsche GT Models
Each Girodisc D2-154 replacement ring is cast and machined in the USA using Girodisc’s proprietary high-carbon iron alloy, developed to withstand extreme heat while maintaining consistent performance. The internal curved vane design functions as a centrifugal air pump, drawing air through the rotor to maximize cooling and prevent fade. Sold as a matched pair, these replacement rings include all new hardware and mount directly to your existing Girodisc aluminum hats for a quick and precise installation.
Features
• Size: 390mm x 32mm
• Direct replacement for Girodisc Porsche 991 / 992 GT3, GT3 RS, and 718 GT4 RS rear rotors
• Proprietary cast iron alloy poured and machined in the USA
• Curved vane internal geometry for optimal cooling and fade resistance
• Includes complete hardware kit for installation
• Reuses Girodisc aluminum hats
• Maintains OEM brake bias and ABS calibration
• Sold/priced per pair
• Not compatible with OEM or other aftermarket hats
Girodisc D2-154 Porsche 390mm Rear Replacement Rotor Rings FAQs
Can I reuse my Girodisc aluminum hats? Yes. These replacement rings are designed to bolt directly onto your Girodisc aluminum hats using the included hardware kit.
Are these compatible with OEM or other brands? No. Girodisc rings are engineered exclusively for Girodisc two-piece rotor systems and will not fit OEM or other aftermarket hats.
What’s included in the kit? Two rear iron rotor rings (left and right) and all new hardware required for installation.
Are the rotors directional? Yes. Each rotor features directional curved vanes to ensure optimal cooling—be sure to install left and right sides correctly.
Do these improve performance over OEM rotors? Absolutely. Girodisc rotors run cooler, resist warping, and offer superior braking consistency under repeated high-temperature conditions compared to OEM discs.
Are they sold as a pair? Yes. The Girodisc D2-154 Porsche 390mm Rear Replacement Rotor Rings are sold and priced per pair and include all necessary hardware for installation.
Maintain your Porsche GT car’s world-class braking performance with Girodisc D2-154 Rear Replacement Rotor Rings—crafted in the USA to deliver unmatched cooling, precision, and endurance on track or street.
