Wilwood ST SX6R Caliper 1.75/1.38/1.38 1.25

This is the Wilwood ST SX6R caliper, part number 120-16039. It's a high-performance brake caliper designed for enthusiasts looking to significantly upgrade their vehicle's stopping power. The SX6R is a six-piston caliper, featuring a unique staggered piston arrangement with three different piston diameters: 1.75 inches for the leading piston, and two 1.38-inch pistons, plus a 1.25-inch trailing piston. This staggered setup is engineered to provide a more balanced and effective clamping force across the brake pad surface, leading to improved braking performance and pad wear characteristics.

Wilwood builds these calipers from forged aluminum, which offers a strong yet lightweight housing. The caliper body is designed for rigidity, helping to minimize flex under heavy braking loads. This caliper is intended for use with larger brake rotors, typically 14 inches or more in diameter, and is a key component in a big brake kit. The SX6R caliper utilizes Wilwood's Smart-Clip hardware for quick pad changes, a practical feature for track use or frequent pad swaps. It's a well-built piece of equipment that represents a substantial step up from most factory calipers.

When considering a caliper like the SX6R, remember that it's part of a larger braking system. You'll need to ensure it's compatible with your chosen rotor size and brake line. This caliper is often paired with Wilwood's matching rotors and brake pads to create a complete, high-performance braking package. Proper installation and bleeding of the brake system are crucial for optimal performance and safety.