Performance Friction two-piece rotors for the 2004-2017 WRX STI (and other four-piston Brembo-equipped Subaru cars) offer lighter weight and better thermal efficiency. By upgrading your brakes with lightweight high performance replacements as opposed to a big brake kit, your factory bias is maintained as well as your ABS efficiency.
PFC's new V3 disc/hat retention system features a patented attachment design that uses a retention ring that holds the hat and disc together. The ring means no need for torque wrenches, and no hassle. The ability to change a disc quickly and efficiently saves time and effort. As well as being convenient, the new V3 technology is much lighter than previous designs, making it easier to put on and pull off, and making the vehicle lighter. The PFC two-piece rotor weighs only 18.1 pounds, compared to 22.5 pounds for the stock rotor. That's a reduction of 4.4 pounds of unsprung, rotating mass per rotor!
V3 two-piece rotor benefits:
Reduced mass on disc connecting flanges, which reduces thermal distortion (more specifically, coning) at race temperatures. Reduced coning allows the pads to sit flatter on the disc, which better utilizes the available radial depth. There is better pad force distribution and the brakes will run cooler, reducing hot spots on the disc. This will also have the benefit of reduced taper wear of the pads.
More heat will be contained in the brake faces because there is less of a heat sink in the flanges. This reduces thermal stress at the ID of the disc and reduces the chance of thermal cracking to occur.
Consistent disc float from race beginning to end. As a race progresses with a bobbin disc, float will often be reduced when a bobbin is no longer sitting square in the disc. Reduced float will increase piston knockback, increase pedal travel and add vibration.
Reduced complexity. The number of brake assembly parts is reduced from 38+ for a bobbin drive disc to just three in a V3 disc assembly
Decreased assembly time. You can assemble a V3 race disc in a matter of seconds.
The hat section of the PFC rotor is made from 6061-T6 aluminum. The disc is made from a proprietary cast iron; the directional multi-vane design maximizes cooling.
Once the PFC two-piece rotor system is in place, simply replace the cast iron rotor rings when needed.
Set of two rotors, left and right.
Fits all 2004-2017 Subaru WRX STI, plus Brembo-equipped Subaru BRZ, and 2020 WRX with Performance Package Brembo brakes. Front only.