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Wilwood 120-11660-BK - Wilwood W4A 4 Piston Forged Aluminum Brake Caliper

Wilwood 120-11660-BK - Wilwood W4A 4 Piston Forged Aluminum Brake Caliper

Wilwood#950-120-11660-BK

W4A 4 Piston Brake Caliper
  • Radial Mount
  • Stainless Steel Pistons
  • 1.25'' / 1.25'' Piston Bore Sizes
  • 1.10'' Brake Disc Width
  • Left Hand, Rear-of-Rotor Mount
  • Black Powder Coat Finish

    Wilwood 120-11660-BK - Wilwood W4A 4 Piston Forged Aluminum Brake Caliper Details

    W4A Brake Calipers

  • Stainless Steel Pistons
  • 1.25'' / 1.25'' Piston Bore Sizes
  • 1.10'' Brake Disc Width



    Product Specifications
    Rotor Compatibility
    Rotor Width:1.1''
    Maximum Rotor Width:1.1''
    Minimum Rotor Width:1.0''
    Maximum Rotor Diameter:15''
    Minimum Rotor Diameter:12.19''
    Brake Pad Specifications
    Brake Pad Type 1:6617
    Brake Pad Type 2:N/A
    Brake Pad Type 3:N/A
    Total Pad Area (in/sq):11''
    Total Pad Volume (in/sq):5.2''
    Piston Specifications
    Piston 1 Bore:1.25''
    Piston 2 Bore:1.25''
    Piston 3 Bore:N/A
    Piston 4 Bore:N/A
    Total Piston Area (in/sq):2.46''
    Mounting Specifications
    Mount Type:Radial
    Mount Side:Left Hand, Rear-of-Rotor
    Mount Center:7.09''
    Mount Hole Size:0.45''
    Mount Height:2.09''

  • Wilwood 120-11660-BK - Wilwood W4A 4 Piston Forged Aluminum Brake Caliper

    Heavy Duty Stopping Power for Road or Track!

    The competition technology that is integrated into Wilwood's W4A six piston forged brake caliper provides outstanding performance, durability and features a configuration design that allows widespread versatility! W4A brake caliper has a radial mount design, two options for piston volume, and a redisigned brake rotor diameter range from 12.19'' to 15.00'' which allows the W6A brake caliper the compatibility for just about every situation of competition duty stopping you need it to provide.

    W4A brake calipers provide the pad wear performance advantages of differential bore pistons with the option for ultimate heat protection using Thermlock piston equipped models. Differential piston bores compensate for leading-edge mechanical loading and temperature variances across the pad face to reduce pad taper wear in sustained high temperature applications. Thermlock pistons block heat transfer from the pads and reduce temperatures in the caliper, fluid, and seals by up to 25% over standard stainless steel pistons. This is the go-to calipers for all types sustained hard braking competition cars.


    Click Here for More Thermolock Piston Details
    The W4A body is the product of FEA computer design and stress flow forging technology. FEA technology allows the designer to test the prototype in a computer environment to determine the optimal structural design within the dimensional parameters of the component. Stress flow forging produces a part with the internal grain structure of the metal aligned in the direction of the flow of the body contour. The results are a caliper with superior clamping efficiency and ultimate strength against fatigue, stresses, and distortion under load.

    The performance of the W4A is enhanced with SRS bridge plates, snap-ring locked pad retainer pins, recessed two-piece bleed screw assemblies and dampen mounted fluid transfer tubes. SRS bridge plates eliminate all bridge wear caused by pad gouging. The spring-loaded action of the plates also eliminates pad rattle. Snap ring clips lock the pad pins in place to provide positive retention and allow easy service without caliper removal. The bleed screws are recess mounted for protection against impact and debris. The fluid tubes are dampen mounted to protect them from fatigue or damage from vibration or debris. Calipers are anodized in high luster black to protect from corrosion and maintain their high-tech appearance.
  • W4A brake calipers are available front-of-rotor or rear-of-rotor mount design
  • Available in differential bore or standard symmetrical bore piston configurations
  • Stainlees Steel or Thermolock pistons
  • Fits rotors from 12.19'' to 15.00'' in diameter, and widths from 1.10'' to 1.25''
  • Calipers weigh only 7.50 pounds



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