Wilwood Caliper-GP320-RH 1.25" Pistons, 0.81" Disc

GP320 Caliper

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.

Pistons

Piston Count: 4
Piston Area (in²): 2.46
Piston Type: Stainless
Dust Boot: No

Rotor Dimensions

Rotor Width(in): 0.81
Rotor Diameter(in): 11.5

Pad Dimensions

Pad Area (in²): 3.65
Pad Volume (in³): 1.03

Duty Rating & Material

Material: Aluminum
Weight(Lbs): 2.1

Colors & Finish

Color : Ano
Finish: Type III Ano

Mounting

Mount Center(in): 3.5

Mount Position

Mount Side: Right Hand
Mount Type: Lug

Product Specifications:

Rotor Compatibility

Rotor Width(in): 0.81
Maximum Rotor Width(in): 0.81
Minimum Rotor Width(in): 0.75
Maximum Rotor Diameter(in): 11.5
Minimum Rotor Diameter(in): 9

Piston Specifications

Piston 1 Bore(in): 1.25
Piston 2 Bore(in): 1.25
Total Piston Area (in²): 2.46

Brake Pad Specifications

Brake Pad Type 1: 6211
Brake Pad Type 2: N-A
Brake Pad Type 3: N-A
Total Pad Area (in²): 3.65
Total Pad Volume (in³): 1.03

Mounting Specifications

Mount Type: Lug
Mount Side: Right Hand
Mount Center(in): 3.5
Mount Hole Size(in): 0.39
Mount Height(in): 1.63
Inlet Thread Size: 1/8-27 NPT