Wilwood Front Dynapro Radial Hub-Rotor Conversion for Chevrolet Tri-Five ProSpindle Cars (1955–1957), Black and Drilled/Slotted / 12.19 Inch

Black calipers and 12.19-inch SRP drilled & slotted rotors are the selected configuration. This Narrow Dynapro Radial front brake conversion combines four-piston calipers, 12.19-inch rotor rings, separate hats and replacement aluminum hubs. It is built around the Wilwood two-inch-drop ProSpindle interface. Wilwood Engineering, founded in 1977 by Bill Wood, is based in Camarillo, California. The company makes disc brake systems and components for motorsport, street-performance and specialized applications, including calipers, brake rotors, master cylinders, valves, fittings and brake lines. Each component must suit the surrounding brake system.

Technical Details

• Order specification: manufacturer part number 140-16907-D; quantity one brake kit.
• The piston diameter specification is 1.75, 1.75 inches, paired with BP-10 brake pads.
• Hats are made from aluminum with a black e-coat surface treatment. Their offset dimension is 1.430 inch.
• Aluminum hubs, bearings and seals are supplied. Wheel pattern choices: 5 x 4.50, 5 x 4.75 inches, with 1/2-20 studs.
• Hydraulic inlet: 1/8-27 NPT.
• Nominal wheel minimum: 15 inches; verify the complete caliper profile against the wheel drawing.
• Flexlines are not included. Choose the required hydraulic hoses and adapters separately.
• Pads and mounting hardware are included. Spindles, master cylinder and brake booster are separate.
• Brake rotor specification: SRP Drilled Rotor, with SRP drilled & slotted friction faces. Overall size is 12.19 × 0.81 inches. Material: Iron.
• Radial-mounted Dynapro Radial Mount calipers are supplied. Each has 4 pistons in stainless, with black powder coat on the caliper body.

Fitment & Compatibility

Wilwood ProSpindle 831-16660 is the required front spindle and is sold separately. This Dynapro assembly places new hubs and 12.19-inch rotor/hat units on that spindle, with a published 0.34-inch outward track change per side. Use the original steering arms and their specified hardware. The vehicle rows cover 1955–1957 Bel Air, Nomad, One-Fifty, Sedan Delivery and Two-Ten, with Del Ray listed for 1957. Check the hub wheel pattern, hose selection and 15-inch wheel envelope. Read the fitment table below for the exact year and option combination; do not apply one row's restrictions to another vehicle.

For help selecting the correct brake package, give PMB Performance the vehicle details and measurements of the installed hardware. Our 20+ years of parts experience help resolve fitment beyond a model name alone.

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.