Fitment questions?
Call (855) 786-7101 or text (801) 304-3141.
Real people. Real answers.
Product details
Type III Anodized finish and 1.75/1.38/1.38-inch bores distinguish this Wilwood Grand National GN6R configuration. It is a right-hand 6-piston brake caliper for 1.38-inch-wide rotors, with 7.09-inch radial attachment centers. Wilwood Engineering was founded by Bill Wood in 1977 and is based in Camarillo, California. The company makes disc brake systems and components, including calipers, rotors, master cylinders, valves, fittings and brake lines for motorsport, street-performance and specialized applications.
Technical Details
- Manufacturer part number: 120-13946
- Component: Wilwood Grand National GN6R; one caliper
- Rotor width: 1.38-inch nominal; 1.25–1.38-inch permitted range
- Rotor diameter range: 12.19–13.06 inches
- Mounting: Right hand; Radial; 7.09-inch centers; 0.45-inch mounting holes
- Mount height: 2.33 inches
- Piston arrangement: 6 pistons; 1.75/1.38/1.38-inch bores; stainless steel
- Hydraulic piston area: 5.40 square inches, as specified by Wilwood
- Pad shape: Wilwood type 7520; compound selected separately
- Body and finish: Forged aluminum; Type III anodized
- Dust boots: No
- Fluid inlet: 1/8-27 NPT
Fitment & Compatibility
Compare the existing caliper’s piston area, rotor capacity and mounting pattern. Matching the body family alone does not guarantee that the replacement will clear the wheel or preserve pedal travel.
This listing covers one caliper. Match the brake pads, rotor, hose and mounting arrangement to the complete brake system.
The six-piston GN6R uses radial attachment, a removable center bridge and type 7520 pads. Matching bracket kits adapt the caliper to earlier Grand National mounting layouts; the 7.09-inch radial centers are not the bracket-to-spindle spacing.
PMB Performance has over 20 years of brake and parts experience. Send us the caliper specifications, rotor measurements and bracket details if you need help selecting the correct component.
