Porsche 991 Big Brake Kits

991xGTX-F Front BBK

100% direct bolt-on front BBK for the Porsche 991.1 and 991.2 lower trim models up to the GTS model. The same kit is also compatible with the 981/718 Boxster and Cayman models. Calipers are sourced from the GT3/GT4 (red/iron rotor variants) and restored using new seals, boots, and aluminum pistons. Titanium pucks or OEM ceramic puck pistons are optional. Discs are 380x34mm 5-lug sized to the GT3/GT4 models. Not directly compatible with centerlock hubs. This front kit pairs well with either the 991xGTX-R 4 piston rear brake kit or the 991 350mm rear rotor/pad upsize kit.

Calipers: Porsche GT3/GT4 6-Piston

Disc Size: 380x34mm

Brackets: Tustin Garage 6061-T6

Pricing: $2550 USD w/2-Piece Lightweight Iron Discs

Pads: Porsche 991 GT3

Finish: 2-Stage Powdercoat (Base Color + Logo + Clear Top Coat)

991xGTX-R Rear BBK

100% direct bolt-on rear BBK for the Porsche 991.1 and 991.2 lower trim models up to the GTS model. Calipers are sourced from the GT3/GT4 (red/iron rotor variants) and restored using new seals, boots, and aluminum pistons. Titanium pucks or OEM ceramic puck pistons are optional. Discs are custom offset 360x28mm 5-lug specifically desgined for fitment with the larger GT3/GT4 4 piston rear calipers. The rotor annulus is based off the 992 models which allows for a larger brake pad than factory base pads for additional clamping force. Not directly compatible with centerlock hubs. This front kit pairs well with the 991xGTX-F 6 piston front brake kit to achieve OEM-level brake bias.

Calipers: Porsche GT3/GT4 4-Piston

Disc Size: 360x28mm

Brackets: Tustin Garage 6061-T6 spacers

Pricing: $2350 USD w/2-Piece Lightweight Iron Discs

Pads: Porsche 992

Finish: 2-Stage Powdercoat (Base Color + Logo + Clear Top Coat)

991 350mm Rear Rotor/Pad Upsize Kit

100% direct bolt-on rear rotor upsize kit for the Porsche 991.1 and 991.2 lower trim models with factory 330x28mm rotors. Discs are Porsche 992-sized 350x28mm 5-lug. The larger disc annulus size allows for a direct drop-in of the larger 992 rear pads into the OEM rear 991 calipers. The larger rotor diameter and brake pad size increases brake torque and clamping force. This rear rotor upsize kit is a great option for those that want to install the 991xGTX-F 6 piston front brake kit but retain the rear factory caliper.

Calipers: N/A

Disc Size: 350x28mm

Brackets: Tustin Garage 6061-T6 spacers + extended caliper bolts

Pricing: $950 USD w/2-Piece Lightweight Iron Discs

Pads: Porsche 992

Finish: N/A

© 2026 Tustin Garage. All rights reserved.