These Girodisc D1-154 front replacement braking surfaces (410 × 36 mm) allow you to replace the braking surfaces on your Porsche 911 (991) GT3, GT3 RS, and GT2 RS with carbon-ceramic rotors (2013–2019), Porsche 718 (982) Cayman GT4 RS with carbon-ceramic rotors (2021+), while retaining the compatible hubs after inspection. These cast-iron pads maintain the floating mounting’s functionality and facilitate maintenance of a braking system subjected to repeated stress. Sold in pairs, without hubs.
The curved internal cooling fins channel air through the rotor to dissipate heat during repeated braking. The floating mounting limits stresses caused by thermal expansion differences between the rotor and the caliper housing and helps the rotor center itself between the brake pads, maintaining consistent contact when hot.
New brake pads must be installed with new discs or rotors. Their shape and compound must match the mounting configuration, cast material, and intended use; follow the specific requirements for this part number and perform the prescribed break-in procedure.
Each application is subject to its specific brake system configuration, calipers, and any requirements for brake pads or spacers. Please verify these conditions before ordering.
Choose brake pads whose shape is compatible with the calipers, the track, and/or the D1-154 rotor, and whose compound is suitable for sport driving or track use. The Endless, pagid Racing, or Ferodo Racing ranges may be considered after verifying the appropriate part number.
For intensive use, we recommend compatible aviation-grade flexible hoses and high-performance brake fluid that meets the vehicle’s specifications, along with proper bleeding and fluid replacement. This recommendation complements the mounting, which is compatible with the original hydraulic system.
When worn, replace the pads with the part number compatible with your existing rotors. Reusing a rotor for up to three pad replacements is subject to inspection of its condition, its mountings, and the mounting instructions; this number does not constitute a guaranteed service life. Use a new mounting each time you replace the pads.
What are the sizes of the D1-154 tracks for my vehicle? The part number shown measures 410 × 36 mm and mounts to the front axle. The track height, mounting bracket, and cups must also be compatible with the mounting.
Is the product sold in pairs? Yes. It includes a left and a right component for the same axle. The brake shoes are not included.
Do I need to replace my vehicle’s brake pads?Yes. Always install new brake pads with new brake discs or new braking surfaces. Use a compound suitable for cast iron and your specific use. Use the Porsche 911 (991) GT3 brake pad shape for cast-iron brakes, which is shorter radially than the PCCB pad.
How do I identify the left and right sides? Girodisc rotors come with a label attached to each rotor: LEFT for the left side and RIGHT for the right side, as viewed in the direction of travel. On a left-hand-drive vehicle, “LEFT” corresponds to the driver’s side and “RIGHT” to the passenger side. Follow these labels and the instructions. On models with curved internal fins, the rolling direction depends on this internal ventilation; the surface grooves alone are not sufficient to determine the side.
How do I break in this mounting on my vehicle? Follow the Girodisc procedure and the brake pad manufacturer’s instructions to build up an even transfer ply. The PDF documents below detail installation and break-in.
We have included two PDF documents below: an instruction manual for installing and running in the discs, and an instruction manual for installing new tracks on existing bowls. Consult the document that applies to your specific task before you begin.
