The GP 320 billet four piston caliper is a compact, high efficiency performer. Weighing just 1.70 pounds, it was purpose built as an upgrade with increased pad size over two piston calipers on lightweight open wheeled racecars. The GP 320 is also well suited to other performance and racing applications including, but not limited to karts, motorcycles, mini-sprints, and formula sports racers. The GP 320 bridge configuration will accommodate rotors between .75" and .81" thick, with overall diameters between 9.00" and 11.50".
Caliper is full CNC detail machined from premium alloy billet. FEA structural analysis technology was employed to develop a design that minimizes weight and maximizes rigidity against deflection. Full width bridges are reinforced with four, high strength steel cross bridge bolts. The cross bridge bolts are coated for corrosion resistance and provide added resistance to deflection and body separation under high loads. Internal fluid ports with a single outboard bleeder provide quick and effective evacuation of gasses and spent fluid.
Clamping force is generated by four, 1.25" diameter, stainless steel pistons. The clamping force is spread evenly over the length of the pad to minimize backing plate deflection and promote balanced pad wear. The overall piston bore area provides an increase in clamping force over similar range two piston calipers. Stainless steel is used to resist corrosion and retard the heat transfer from the brake pad to the caliper body, seals, and fluid.
Additional Notes
The GP 320 uses Wilwood type 6211 brake pads. The pads measure .44" (11,2mm) thick with an overall length of 2.74" ( 69,6mm). This represents nearly a 50% increase in pad area over some of the popular two piston calipers used on similar applications. The 6211 pad is available in PolyMatrix "H" compound which provides predictable engagement, high friction, long wear, and extreme high temperature fade resistance in the harshest conditions. Other Wilwood performance enhancements include high temperature square faced bore seals that provide a wide sealing area with positive piston retraction on release. Quick-Clip retention pins provide easy access for pad service without caliper removal. The calipers are finished in Type III hard anodizing for protection against corrosion and the elements.
About Wilwood Engineering
Wilwood Engineering designs and manufactures high-performance disc brake systems. Since the company’s inception in 1977 by Bill Wood, we have developed a substantial matrix of brake components and engineering techniques that allow us to quickly and reliably create brake systems for almost any application. Our core ability is the rapid development of custom engineered brake systems using a combination of off-the-shelf and custom components. In addition to designing and manufacturing brakes for all types of competitive motor sports, Wilwood also manufactures brake systems and components for agricultural equipment, industrial applications, utility vehicles, snowmobiles, quads, motorcycles and military vehicles.
With headquarters in Camarillo, California, Wilwood employs approximately 250 people. We have on-shelf stock of more than 300 different brake calipers, 200 rotor designs, 100 master cylinder designs and a wide assortment of brackets, fittings, valves and brake lines. Our off-shelf brake calipers range in size from tiny calipers used on go-carts and light duty industrial equipment, to heavy duty original equipment brakes for the U.S. military Humvee.
Wilwood's engineering department uses the latest computer-aided design and manufacturing techniques in conjunction with finite element analysis, dynamic test and cycle test equipment, to find high-performance and reliability solutions for the most difficult braking tasks. Our extensive inventory of proprietary on-the-shelf components allow us to provide cost-effective solutions for unique brake applications.
Wilwood is ISO 9000 compliant and has extensive experience maintaining quality levels of 100ppm or less for original equipment manufacturers.