Wilwood Front FNSL6R Conversion with 14-Inch GT Slotted Rotors and Black Calipers, Chevrolet Tri-Five ProSpindle Cars (1955–1957)

The 14.00-inch FNSL6R front conversion uses six-piston Superlite calipers, separate rotor hats and aluminum hubs for the Tri-Five ProSpindle layout. This larger-rotor version requires the matching wheel envelope and spindle geometry. Black calipers and 14.00-inch GT slotted rotors are the selected configuration. Founded by Bill Wood in 1977 and based in Camarillo, California, Wilwood Engineering designs and manufactures disc brake systems and components for motorsport, street-performance and specialized applications. Its range includes calipers, brake rotors, master cylinders, valves, fittings and brake lines, chosen to match the complete system.

Technical Details

• The Wilwood manufacturer part number is 140-16909. This product is sold as a kit.
• The black powder coat caliper bodies are Forged Narrow Superlite 6R units with 6 pistons. Stainless pistons and radial mounts are specified.
• 14.00-inch rotors are supplied in the GT slotted configuration; the published thickness is 1.10 inch. These rotors use Spec-37 Iron.
• Friction material supplied is BP-20; the caliper bore measurements are 1.62, 1.12, 1.12 inches.
• A 1.100-inch hat offset locates each rotor ring. Hats use aluminum construction and black e-coat finish.
• Replacement hubs are aluminum and come with the specified bearings/seals. Wheel drilling: 5 x 4.50, 5 x 4.75 inches; studs: 1/2-20.
• Caliper inlet thread is 1/8-27 NPT.
• Published minimum rim diameter is 18 inches. Use the template to check spoke clearance as well.
• Provide suitable flexible hoses and caliper/chassis fittings; the brake kit does not supply flexlines.
• Supplied items include the pads and mounting fasteners; no replacement spindle, master cylinder or booster is included.

Fitment & Compatibility

The required Wilwood Tri-Five ProSpindle is the separately sold 831-16660 kit; original steering arms are reused. This Superlite configuration uses 14.00-inch rotors and has a published 0.23-inch outward hub offset on each side, making wheel track and spoke clearance part of the selection. It covers the listed Bel Air, Nomad, One-Fifty Series, Sedan Delivery and Two-Ten Series 1955–1957 plus Del Ray 1957. Match the hub stud pattern and 18-inch wheel drawing and provide suitable hoses. Use the complete application table below to check the individual year, model, submodel, original brake configuration and attached notes.

PMB Performance brings 20+ years of parts and fitment experience to brake selection. Send the actual hub or spindle details, existing brake configuration and wheel measurements for help checking this combination.

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.