Wilwood Dynalite Internal 4-Piston Caliper in Polished, 5.25-Inch Lug Attachment

Polished finish and 1.62-inch bores distinguish this Wilwood Forged Dynalite Internal configuration. It is a 4-piston brake caliper for 0.38-inch-wide rotors, with 5.25-inch lug attachment centers. Wilwood Engineering was founded by Bill Wood in 1977 and is based in Camarillo, California. The company makes disc brake systems and components, including calipers, rotors, master cylinders, valves, fittings and brake lines for motorsport, street-performance and specialized applications.

Technical Details

• Manufacturer part number: 120-13841-P
• Mounting: universal side configuration; Lug; 5.25-inch centers; 0.39-inch mounting holes
• Mount height: 2.03 inches
• Rotor width: 0.38-inch nominal; 0.25–0.38-inch permitted range
• Rotor diameter range: 10.00–13.06 inches
• Pad shape: Wilwood type 7112; compound selected separately
• Piston arrangement: 4 pistons; 1.62-inch bores; stainless steel
• Hydraulic piston area: 4.12 square inches, as specified by Wilwood
• Body and finish: Forged aluminum; Polish
• Fluid inlet: 1/8-27 NPT
• Dust boots: No
• Component: Wilwood Forged Dynalite Internal; one caliper

Fitment & Compatibility

Compare the existing caliper’s piston area, rotor capacity and mounting pattern. Matching the body family alone does not guarantee that the replacement will clear the wheel or preserve pedal travel.

This listing covers one caliper. Match the brake pads, rotor, hose and mounting arrangement to the complete brake system.

This four-piston Dynalite uses internal fluid transfer in a spacerless body. Its 5.25-inch mounting pattern is only one compatibility dimension: rotor position, body clearance and hydraulic area also need to agree.

Ask PMB Performance for help comparing this caliper with your existing assembly. Our over 20 years of experience are most useful when you provide rotor size, mounting details and the current piston configuration.