Got a big shipment of Porterfield pads in... R4-S for fast street and autocross, and R4's for the track junkie!

Porterfield R4:


Designed specifically for heavy-duty motorsports. The carbon based semi-metallic R-4 materials allow the pad to absorb tremendous amounts of heat and dissipate it at very even rate. Carbon Kevlar material warms up to race temperature quickly, which is quite helpful during restarts, and when track time is limited. When used with cast iron and steel alloy rotors, the R-4 compound requires minimal bed-in period. Throughout the entire heat range, the carbon kevlar material will give extremely consistent modulation and predictably. This is truly the most rotor friendly racing brake pad material ever. Good for road courses, oval track, rally, vintage racing, autocross, club events or professional racing events.
While intended for heavy duty use, we have found this pad to still work okay for the street. It is dusty, though!

Porterfield R4-S:


For high performance and heavy-duty street conditions. Perfect for prolonged everyday street use while also being capable of tolerating the most severe street use without any fade. Rotor friendly, of course. The R4-S friction level will give you an impressive increase in stopping ability with very minimum pedal effort. R4-S compound has the absolute lowest noise and dust levels, far below OEM equipment or any other high performance brake material. Good for autocrossing, some drivers' schools, and rallies.
The R4-S is NOT recommended for full-on track use, per Porterfield.