Rear Brake Upgrade for Track and Fast Road Performance

This Girodisc rear rotor kit is a direct replacement for the factory 380mm rear steel discs fitted to Porsche 991 GT3 and GT3 RS models with OEM red calipers. As a lightweight, 2-piece floating design, it significantly improves cooling efficiency, reduces unsprung weight, and enhances pedal response — especially under repeated high-temperature use on track.

Paired with the front Girodisc upgrade, this completes a fully balanced, high-performance braking setup designed to withstand the rigours of endurance racing and spirited road driving.

Why Upgrade to Girodisc?

• Lower unsprung mass for more agile suspension response

• Curved vane design promotes better cooling and thermal control

• Motorsport-level durability with reduced cracking under repeated heavy braking

• Designed for compatibility with popular pad compounds like Ferodo DS3.12, Endless ME20/22, or PFC 08/11

🔧 Designed specifically for 991 GT3 and GT3 RS models equipped with factory steel brakes (red calipers). Not suitable for PCCB (ceramic) equipped models.

Key Features

• 2-piece floating steel disc (iron rotor) construction

• CNC-machined 6061-T6 aluminium bell, anodised for corrosion resistance

• 380mm diameter – direct OEM replacement for factory rear steel brakes

• Directional curved vanes for effective heat management

• Fully made in the USA

• Works with OEM calipers and brake lines

• Ideal for high-performance road use, track days and endurance racing

Compatibility

• Porsche 991.1 GT3 (factory steel brakes only)

• Porsche 991.2 GT3 (factory steel brakes only)

• Porsche 991.1 GT3 RS (factory steel brakes only)

• Porsche 991.2 GT3 RS (factory steel brakes only)

⚠️ Not suitable for vehicles with PCCB carbon ceramic brakes (yellow calipers).

Matching Front Kit Available

We also offer the front 380mm Girodisc steel rotor upgrade for steel brake cars. For best results and braking balance, we strongly recommend replacing front and rear rotors together...

Girodisc Front Steel Disc Upgrade – 380mm – Porsche 991 GT3 / GT3 RS (Steel Brakes)

Recommended Supporting Upgrades

• Motorsport-grade brake pads (e.g. Ferodo DS3.12, Endless ME20/22, PFC 08/11)

• Braided brake lines

• High-temp brake fluid (Motul RBF 660, Endless RF-650)

Serviceability & Replacement

Once the Girodisc kit is installed, simply replace the disc/rotor when worn. New hardware is included with replacement discs, and the aluminium bells do not require replacement.

Sold/priced per pair.