Wilwood Front Brake System with Red Superlite 6R Calipers, 14-Inch GT Rotors and Hubs, Listed GM Second-Generation AFX ProSpindles (Listed 1970–1990 Applications)

Red Superlite 6R calipers and 14-inch GT slotted rotors make up this front hub conversion for the required second-generation Wilwood AFX ProSpindles. BP-20 pads, aluminum hats and hubs are supplied; the spindles and brake hoses are not. Read the complete GM application row, check the wheel's actual clearance profile and match the master-cylinder/rear-brake arrangement to the six-piston front calipers before installation. Based in Camarillo, California, Wilwood Engineering was founded by Bill Wood in 1977. Its disc brake systems serve motorsport, street-performance and specialized applications. The range includes calipers, rotors, master cylinders, valves, fittings and brake lines, with each component chosen for its role in the complete brake installation.

Technical Details

• Manufacturer part number: 140-15983-R. 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, red powder coat finish.
• Published piston bores: 1.62, 1.12, 1.12 inches. Supplied pad compound: BP-20.
• Caliper hydraulic inlet: 1/8-27 NPT.
• Rotor specification: 14.00-inch outside diameter × 1.10-inch thickness; GT slotted faces. Spec-37 Iron construction; GT 72 Curved Vane design; published vane configuration: 72 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: 18 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: 220-10509.

Fitment & Compatibility

Use this kit on the listed GM applications equipped with Wilwood second-generation AFX ProSpindles. Do not assume that original spindles or the earlier AFX spindle are interchangeable. Match the model, production year and spindle option in the application table, then verify the installed spindle, hub bolt circle, full wheel seating and actual spoke/barrel clearance. Match the front caliper volume and pad compound to the master cylinder and rear brakes, and supply suitable braided flexlines separately. Use the complete application table below for the individual year, submodel, brake configuration and note attached to each entry.

With over 20 years of parts and fitment experience, PMB Performance can help compare the required mounting interface with the vehicle build. Share spindle or axle measurements and wheel information before ordering if anything is uncertain.

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.