Wilwood Caliper-Forged Superlite 4R-ST-L/H - 1.88/1.62in Pistons 1.25in Disc

This Wilwood Forged Superlite 4R-ST brake caliper kit includes one caliper designed for the left or right side. It features differential bore pistons, specifically 1.88 inches for the leading piston and 1.62 inches for the trailing piston, and utilizes Thermlock® pistons to combat heat transfer. These calipers are built for sustained hard braking in demanding applications like dirt and asphalt ovals, off-road, rally, and road course racing.

The differential bore piston design helps manage pad taper wear by compensating for leading-edge mechanical loading and temperature differences across the pad surface, especially under sustained high temperatures. The Thermlock® pistons are a notable feature in the ST models, as they actively block heat from reaching the caliper body, fluid, and seals, potentially reducing temperatures by up to 25% compared to standard stainless steel pistons. The caliper body itself is finished with a wear-resistant Type III hard anodize for added durability.