STR6 Radial Mount Caliper

Wilwood's STR radial mount caliper is the result of extensive testing and development focused on overcoming racing's most demanding high temp conditions. There are no brake tests tougher than stock cars racing on the legendary short tracks and road courses like Martinsville and Watkins Glen. The STR caliper is engineered to maximize braking under these extreme conditions.

The development of the STR caliper began with FEA structural design and stress analysis. The goal was to achieve a highly efficient clamping force with the lowest amount of deflection and fluid displacement resulting in a firm, consistent pedal feel for the driver. The caliper accommodates the widest, most thermally efficient rotor ever built. Extensive prototype testing and development has minimized structural deflection and volume displacement on this caliper and support components. The STR easily outperforms other short track systems in comparison testing with vastly superior heat management.

Weighing just 10.38 pounds, the STR features a six piston differential bore configuration that is easily matched with common pedal ratios and master cylinder bore sizes. The size, and location of each piston effectively varies the pressure load to compensate for natural temperature changes that occur over the length of the pad. This assures flat pad wear during extreme heat build-up on long green flag runs. Wilwood's exclusive Thermlock® T2 pistons dramatically reduce heat transfer from the pads to the caliper body, piston seals, and fluid. This not only maintains safe and manageable caliper operating temperatures, it also keeps the heat in the pads where it can be properly removed by the rotor. A total of ten pre-loaded bridge bolts provide unmatched strength. The center bridge bar provides additional strength, and also accommodates quick and easy pad changes without caliper removal. Two-piece bleed assemblies enable hot bleeding without the risk of seat damage in the caliper body. All fluid tubes are vibration dampened to resist stress fractures and reduce the possibility of damage from track debris. Not only is this caliper stronger than mono-block designs, it is far easier and faster to service at the track.