Girodisc Rear Steel Disc Conversion – 390mm – Porsche 991 GT3 / GT3 RS / GT2 RS / 718 GT4 RS - Clubsport Garage

Girodisc Rear Steel Disc Conversion – 390mm – Porsche 991 GT3 / GT3 RS / GT2 RS / 718 GT4 RS

By Girodisc
£1,995.00
Available – Dispatched within 3–5 Days
Worldwide Shipping
Official Dealer
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Product Description

The Girodisc 390mm Rear Steel Disc Conversion Kit is a direct-fit rear brake disc conversion for Porsche GT models originally equipped with PCCB carbon ceramic rear brakes. Also referred to as iron rotors, this kit replaces the factory 390mm carbon ceramic rear discs with high-performance 2-piece floating steel rotors.

Ideal for owners who want to preserve expensive OEM ceramics, reduce long-term running costs or achieve more predictable track braking performance, the Girodisc rear conversion offers improved thermal stability, consistent pedal feel and compatibility with motorsport brake pad compounds.

Each rotor uses a lightweight 6061-T6 aluminium hat, anodised for corrosion resistance, paired with a steel / iron rotor ring. The directional curved vane design helps move cooling air through the disc during repeated heavy braking, supporting consistent performance during fast road, endurance and circuit use.

The kit retains compatibility with the OEM yellow PCCB calipers and factory brake lines. For best performance and brake balance, converting both front and rear discs together is strongly recommended.

Sold and priced as a rear axle pair.

⚠️ Only suitable for vehicles originally equipped with PCCB rear brakes. Not compatible with models that came with steel brakes from the factory.

Front Conversion Also Available

This rear kit is designed to be used in conjunction with the matching 410mm Girodisc front conversion kit, available separately...

Girodisc Front Steel Disc Conversion – 410mm – Porsche 991 GT3 / GT3 RS / GT2 RS / 718 GT4 RS

Further information below.

Key Features
  • Girodisc 390mm rear steel disc conversion kit
  • Also referred to as iron rotors
  • Designed to replace factory PCCB carbon ceramic rear discs
  • Rear axle fitment
  • 390mm rear disc diameter
  • Direct-fit replacement for OEM PCCB rear discs
  • For vehicles originally fitted with PCCB rear brakes
  • 2-piece floating steel rotor design
  • Lightweight 6061-T6 aluminium hats
  • Anodised for corrosion resistance
  • Directional curved vane cooling
  • Improved thermal stability for track use
  • Consistent braking performance under repeated heavy braking
  • Improved pedal feel and control compared with worn or heavily used ceramics
  • Reduced long-term maintenance costs compared with replacement ceramics
  • Fully CNC machined in the USA
  • Compatible with OEM yellow calipers
  • Compatible with OEM brake lines
  • Suitable for fast road use, endurance racing and circuit driving
  • Compatible with motorsport pad compounds including Ferodo DS3.12, Endless ME20 / ME22 and PFC 08 / 11
  • Matching 410mm Girodisc front conversion kit available separately
  • New hardware included with replacement discs
  • Aluminium bells do not require replacement when changing worn rotor rings
  • Sold and priced as a pair

Vehicle Compatibility
  • Only suitable for vehicles originally equipped with PCCB rear brakes.
  • Porsche 991.1 GT3
  • Porsche 991.2 GT3
  • Porsche 991.1 GT3 RS
  • Porsche 991.2 GT3 RS
  • Porsche 991.2 GT2 RS
  • Porsche 718 Cayman GT4 RS
  • Not compatible with models that came with steel brakes from factory.
  • Designed to replace OEM 390mm PCCB rear discs while retaining the OEM yellow calipers and brake lines.
  • For optimal performance and brake balance, use with the matching 410mm Girodisc front steel disc conversion kit.
  • Please confirm vehicle model, brake package, rear disc size, caliper colour and whether the vehicle was originally fitted with PCCB before ordering.

What's Included
  • Pair of Girodisc 390mm rear steel discs / iron rotors
  • Left rear 2-piece floating rotor
  • Right rear 2-piece floating rotor
  • Lightweight 6061-T6 aluminium hats
  • Anodised aluminium bell / hat assemblies
  • Steel / iron rotor rings
  • Floating rotor hardware
  • Brake pads, brake lines, front rotors, brake fluid and fitting consumables are not included unless supplied separately

FAQs

What is the Girodisc rear steel disc conversion kit designed for?

It is designed to replace factory 390mm PCCB carbon ceramic rear discs with 2-piece floating steel / iron rotors.

Are these front or rear discs?

This listing is for rear discs / rotors.

What size are the rear discs?

These are 390mm rear discs.

Are they sold individually or as a pair?

They are sold and priced as a pair.

Which vehicles does this kit fit?

It fits selected Porsche GT models originally equipped with PCCB rear brakes, including 991 GT3, 991 GT3 RS, 991.2 GT2 RS and 718 Cayman GT4 RS applications.

Is this kit suitable for factory steel brake cars?

No. This kit is only suitable for vehicles originally equipped with PCCB rear brakes.

Will it work with OEM yellow calipers?

Yes. The kit retains compatibility with the OEM yellow PCCB calipers.

Do I need to change the brake lines?

No. The kit retains compatibility with the OEM brake lines.

Why convert from PCCB to steel discs?

Steel discs can offer better thermal stability for repeated track use, improved pedal feel and lower long-term replacement costs compared with carbon ceramic discs.

Should I convert the front and rear discs together?

Yes. For optimal performance and brake balance, front and rear conversion is strongly recommended.

Which front kit matches this rear conversion?

This rear kit is designed to pair with the matching 410mm Girodisc front steel disc conversion kit.

Which brake pads can be used with these discs?

Suitable motorsport pad options include Ferodo DS3.12, Endless ME20 / ME22 and PFC 08 / 11, depending on intended use.

Can the rotor rings be replaced separately?

Yes. Once the Girodisc kit is installed, only the disc / rotor rings need to be replaced when worn. The aluminium bells do not require replacement.

What should I check before ordering?

Please confirm vehicle model, brake package, rear disc size, caliper colour and whether your car was originally fitted with PCCB rear brakes before ordering.

Shipping & Delivery

Dispatch Times

Most stocked items dispatch within 1–2 business days. Some products may have longer lead times due to special ordering, availability, or build times. If your order contains multiple items, they may be shipped together once all items are ready unless otherwise agreed.

UK & International Shipping

We ship worldwide. Transit times vary depending on destination and courier. Tracking details are provided once your order is dispatched.

Import Duties & International Orders

International customers are responsible for all import duties, taxes, and clearance fees. These are not included in our prices and are outside of our control. Refusal or non-payment of import charges may result in return shipping, handling fees, and customs charges being deducted from any refund.

Damaged Shipments

If your parcel arrives visibly damaged, please refuse delivery or note the damage with the courier. If damage is discovered after opening, contact us immediately with photos. Do not install damaged items, as installation voids courier claims and return eligibility.

Returns

Returns must be authorised before sending anything back. Returns must be requested within 14 days of delivery and returned within 14 days of approval, in unused/uninstalled condition and in original packaging. Some items, including special-order, built-to-order, used, installed, or modified parts, are non-returnable.

Full details are available in our Shipping Policy and Returns & Refund Policy.

Warranty & Disclaimer

Warranty

Most products include a manufacturer’s warranty covering manufacturing defects only. Warranties do not cover wear and tear, improper installation, misuse or neglect, track use, competition or racing environments, labour costs, vehicle damage, downtime, or consequential loss. Warranty outcomes are determined by the manufacturer, not Clubsport Garage. Items must be returned for inspection at the customer’s cost unless agreed otherwise.

Fitment & Installation

Many products are aftermarket components and may require professional installation or minor adjustment. Perfect OEM-level fitment cannot be guaranteed. Professional installation by an experienced workshop is strongly recommended. Installed or used items cannot be returned.

Motorsport Use Disclaimer

Some products are intended for off-road, track, or motorsport use only and may not be legal for road use, for example non-TÜV/DOT-approved parts. It is the customer’s responsibility to ensure compliance with local laws, insurance requirements, and vehicle regulations. By purchasing and installing aftermarket parts, you accept all responsibility for ensuring compatibility, legal compliance, proper installation, and any resulting wear, damage, or failure.

Product Images & Descriptions

Product photos are illustrative and may differ slightly from the item supplied. If specific details are important, please contact us before purchasing.

Full details are available in our Terms of Service and related policy pages.