Repeated high-speed braking demands more than a larger rotor. It demands calipers that maintain control of the pad, friction components that manage sustained heat, and mounting hardware that allows the system to work as temperatures rise. The Alcon / Pro-System BRK.200621 brings those elements together in a complete front-and-rear brake system for the Porsche 992 GT3 and GT3 RS.

Six-piston front calipers work with 390 x 36mm floating rotors, while four-piston rear calipers use 390 x 32mm floating rotors. Application-specific aluminum hats, caliper brackets and brake lines complete the package. Pro-System's dyno-bedding process prepares the friction surfaces before installation, giving the system a controlled start to its service life.

A Complete Brake System for the 992 GT3 and GT3 RS

Alcon's motorsport experience is reflected in the details that matter during a long session: staggered piston diameters, substantial pad thickness and serviceable two-piece rotors. Pro-System brings the calipers, rotors, hats, brackets and friction components together as a vehicle-specific package. This listing includes both axles.

Alcon Competition Calipers

The front six-piston calipers use 27.0 / 31.8 / 38.1mm pistons, with 31.8 / 34.9mm pistons in the four-piston rear calipers. Staggered piston diameters help control pad loading and reduce taper wear. The caliper layout supports quick pad changes without removing the calipers, making inspection and friction changes more practical between sessions.

• Six-piston front and four-piston rear competition calipers
• Catalog caliper weights: 7.3 lb front and 6.0 lb rear, each
• High-temperature seals and stainless steel pistons
• Bolted pad retainers and staggered piston diameters
• Anodized or ENP nickel-plated finish, according to your selection

Floating Two-Piece Rotors

Under hard braking, the iron friction ring becomes much hotter than its aluminum hat. A fully floating attachment allows the ring to expand with less restraint from the mounting, helping it accommodate repeated heating and cooling. Anti-rattle clips control movement within the floating assembly.

The 390mm rotors use 48 directional ventilation vanes to move cooling air through the disc. Front rotor thickness is 36mm; rear thickness is 32mm. The slotted friction faces help keep the pad contact surface clean during use. Separate left- and right-hand rings ensure the directional ventilation is installed correctly.

Two-piece construction also makes the system economical to service over time. Worn friction rings can be replaced while retaining hats that remain within service limits. Catalog rotor weights are 23.4 lb front and 19.6 lb rear, each.

Precision-Machined Hats and Brackets

Lightweight aluminum hats connect the friction rings to the hubs, while dedicated brackets position the calipers over the rotors. The hats and brackets are machined for this application rather than adapted from a generic mounting arrangement. Anodized surfaces provide wear and corrosion resistance.

Dyno-Bedded Friction Components

Pro-System prepares its rotors and supplied pads through a controlled dyno-bedding process. This establishes the friction surfaces before the system is fitted to the car. Follow the supplied installation and operating instructions, particularly when choosing the No Pads option or changing pad compounds later.

Select Pro-System B1 to include the B1 pad sets, or No Pads if you are supplying your own compatible friction material. The documented pad thicknesses are 25mm front and 20mm rear. Pad shape, thickness and compound must match the calipers and intended use.

What's Included

• Two six-piston front calipers and two four-piston rear calipers in the selected finish
• Two 390 x 36mm front rotor assemblies and two 390 x 32mm rear rotor assemblies
• Application-specific rotor hats, caliper brackets and mounting hardware
• Front and rear brake lines
• Fully floating rotor hardware and anti-rattle clips
• Front and rear Pro-System B1 pad sets when the B1 option is selected

Fitment and Wheel Clearance

For Porsche 992 GT3 and GT3 RS applications with center-lock wheels. Check the brake clearance template against your exact wheels before ordering; wheel diameter alone does not establish spoke or barrel clearance. Rotor assemblies arrive pre-assembled. Installation may require trimming the dust or heat shields.

Complete system part number: BRK.200621. ENP denotes nickel plating; select your pad and finish options above.