Wilwood Front Plain-Rotor Hub Conversion for GM Second-Generation AFX ProSpindles, Red Dynapro Four-Piston Calipers and 11.75-Inch Rotors (Listed 1970–1990 Applications)

The plain-rotor red Dynapro kit supplies four-piston front calipers and aluminum hubs for the specified second-generation AFX ProSpindles. Its 11.75-inch vented rings mount through separate adapters, with BP-10 pads included. Confirm the spindle generation before reading the GM vehicle rows as compatible applications. The wheel must seat fully on the hub and clear the assembled caliper; hydraulic hoses are a separate selection. 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: 140-15981-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: Dynapro Radial Mount; 4 pistons; stainless piston material. Radial mounting, red powder coat finish.
• Published piston bores: 1.75, 1.75 inches. Supplied pad compound: BP-10.
• Caliper hydraulic inlet: 1/8-27 NPT.
• Rotor specification: 11.75-inch outside diameter × 0.81-inch thickness; plain faces. Iron construction; Ultralite HP 30 design; published vane configuration: 32 V.
• Supplied hub assembly: Hub - Vented Rotor Offset, aluminum, bare finish.
• Wheel mounting patterns: 5 x 4.50; 5 x 4.75 inches.
• Minimum nominal wheel diameter: 15 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. If any wheel contact surface overhangs the hub face, follow the documented requirement for the separate wheel spacer rather than allowing an unsupported wheel contact area. 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.