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: $2450 USD w/2-Piece Lightweight Iron Discs

Pads: Porsche 991 GT3 (Hawk HPS 5.0)

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 380x30mm 5-lug sized to the GT3/GT4 models. Not directly compatible with centerlock hubs. This rear kit pairs well with the 991xGTX-F 6 piston front brake kit to achieve OEM-level brake bias. This kit is recommended for heavier street/track use due to its larger rotor size and thicker 18mm pad sizing. Rear rotors retain the in-drum parking brake.

Calipers: Porsche GT3/GT4 4-Piston

Disc Size: 380x30mm

Brackets: Tustin Garage 6061-T6 spacers

Pricing: $2500 USD w/2-Piece Lightweight Iron Discs

Pads: Porsche 991 GT3 (Hawk HPS 5.0)

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. This rear kit is recommended for street applications due to the lighter weight 350x28mm rotor and standard 16mm thick brake pads. Rear rotors retain the in-drum parking brake.

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 (Hella Pagid)

Finish: N/A

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