Wilwood Front GT Slotted Rotor and FNSL6R Caliper Kit for Chevrolet Tri-Five ProSpindle Cars (1955–1957), Black / 12.88 Inch

Six-piston FNSL6R front calipers and 12.88-inch rotors join replacement aluminum hubs in this Tri-Five ProSpindle package. Separate hats position the rotor rings around the specifically required Wilwood spindle. Black calipers and 12.88-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

• Order specification: manufacturer part number 140-16908; quantity one brake kit.
• The piston diameter specification is 1.62, 1.12, 1.12 inches, paired with BP-20 brake pads.
• Hats are made from aluminum with a black e-coat surface treatment. Their offset dimension is 1.100 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: 17 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: GT 48 Curved Vane, with GT slotted friction faces. Overall size is 12.88 × 1.10 inches. Material: Spec-37 Iron.
• Radial-mounted Forged Narrow Superlite 6R calipers are supplied. Each has 6 pistons in stainless, with black powder coat on the caliper body.

Fitment & Compatibility

Verify Wilwood 831-16660 two-inch-drop ProSpindles before selecting this 12.88-inch Superlite package. Spindles are purchased separately and the steering arms come from the customer. The original-spindle arrangement is unsuitable. Listed Chevrolet bodies are Bel Air, Nomad, One-Fifty Series, Sedan Delivery and Two-Ten Series for 1955–1957, and Del Ray for 1957. A 0.23-inch per-side outward wheel-track change is published; confirm the new hub pattern and 17-inch wheel template. 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.