If you track your STI hard, it can be a challenge to keep the brake fluid cool, as heat from braking will travel through the pads and into the caliper pistons, then to the brake fluid. Get the fluid hot enough and it will boil, leading to soft -- or nonexistent! -- pedal pressure and seriously scary moments when it comes time to haul the car down from speed.
Evo Corse is an Italian company specializing in competition parts. Their P-DEF brake pad plates -- the acronym stands for Pyroclastic Dynamic Energy Filter -- are designed to greatly reduce the transmission of heat from the pads into the brake calipers. The P-DEF plates install between the brake pads and the caliper pistons, and act as a heat barrier between the hot brake rotors/pads and the rest of the braking system. The proprietary Pyroclast material is the outcome of years of research. It boasts exceptional insulation properties as well as high compression strength.
As a bonus, the small amount of cushion provided by the P-DEF plate can reduce squealing and resonance from the brakes.
Benefits:
Installation notes: The plates install directly behind the brake pads. The P-DEF plates are only about 1mm thick, but confirm clearance before using the brakes; if there is not enough space for pads to clear the rotor with the P-DEF plate in place, you will want to wait until the pads are slightly worn, or you will want to polish a little friction material off the face of the pad to have clearance.
OEM Subaru brake pads for this application have a metal squealer tab on the corner of one pad. You'll want to remove that tab, since the plates do not have a relief for it. You're using this car on track, so you'll be checking your pads frequently anyway, right?
Imported by us directly from Italy.
Sold as a set of four plates, enough for two front brake calipers.
Fits all 2018-2021 Subaru WRX STI. Also 2024+ WRX TR!