Wilwood Front Six-Piston Superlite SRP Hub System for GM AFX ProSpindles, 12.88-Inch Rotors and Black Calipers (Listed 1964–1974 Applications)

Drilled/slotted 12.88-inch Spec-37 rotors and black Superlite 6R calipers define this front brake/hub package. Its six-piston service calipers use BP-10 pads, while separate hats connect the rings to the included aluminum hubs. The application table assumes Wilwood AFX ProSpindles are already installed. Match the hub pattern and wheel drawing, and obtain an appropriate braided-line arrangement separately. Wilwood Engineering was established in 1977 by Bill Wood in Camarillo, California. The company designs and manufactures disc-brake systems and components, from calipers and rotors to master cylinders, valves, fittings and brake lines, for motorsport, street-performance and specialized installations. Each component must match the rest of the brake system.

Technical Details

• Manufacturer part number: 140-15910-D. Quantity: one kit for the stated axle/application.
• Mounting hardware and the specified pads are included. Spindles, master cylinder and brake booster are not supplied.
• Service caliper: Forged Narrow Superlite 6R; 6 pistons; stainless piston material. Radial mounting, black powder coat finish.
• Published piston bores: 1.62, 1.12, 1.12 inches. Supplied pad compound: BP-10.
• Caliper hydraulic inlet: 1/8-27 NPT.
• Rotor specification: 12.88-inch outside diameter × 1.10-inch thickness; SRP drilled & slotted faces. Spec-37 Iron construction; SRP Drilled Rotor design; published vane configuration: 48 CV.
• Rotor hats: aluminum, black e-coat finish; Big Brake Hat - Flared Bell. Hat offset: 1.500 inch.
• Supplied hub assembly: Hub - Hat Mount, aluminum, bare finish.
• Wheel mounting patterns: 5 x 4.50; 5 x 4.75 inches.
• Minimum nominal wheel diameter: 17 inches. The wheel must also clear the actual caliper and rotor profile in the installation drawing.
• Brake hoses are not included. Manufacturer line-kit reference(s), sold separately: 220-7056.

Fitment & Compatibility

Use only with the documented Wilwood AFX ProSpindles on the listed GM A-, F- and X-body applications. The manufacturer identifies the primary groups as 1964–1972 A-body, 1967–1969 F-body and 1968–1974 X-body; individual rows retain their specific year and model limits. The required aftermarket spindles are not included, and original spindles are not an equivalent interface. Verify wheel-bolt pattern, hub contact surface, caliper clearance and the completed hydraulic balance. Use the complete application table below for the individual year, submodel, brake configuration and note attached to each entry.

PMB Performance has over 20 years of experience working with parts and fitment details. Provide the actual brake hardware, mounting dimensions and wheel measurements when requesting help with this conversion.

Manufacturer documentation: Installation instructions.

Manufacturer Warning

Applicable to brake pads only: Wilwood warns of exposure to arsenic, cadmium, hexavalent chromium compounds, lead, nickel, cobalt and antimony trioxide, chemicals known to California to cause cancer or reproductive harm. More information: P65Warnings.ca.gov.