Wilwood Right GTB Slotted Rotor, 15.50 x 1.38-inch with 10.25-inch Mount Circle

This right-hand GTB rotor uses a 10.25-inch attachment circle, larger than the patterns on neighboring GT60 sizes. Its 15.50 x 1.38-inch friction section and 9.64-inch registration require the corresponding hat and caliper arrangement. Camarillo, California is home to Wilwood Engineering, founded in 1977 by Bill Wood. The company designs and manufactures disc brake systems and their calipers, brake rotors, master cylinders, valves, fittings and brake lines. Across motorsport, street-performance and specialized applications, these components must be matched as parts of a complete braking system.

Technical Details

• Manufacturer part number: 160-13789-GTB
• Outside diameter / width: 15.50 inches diameter x 1.38 inches wide
• Material specification: Spec-37 Iron
• Friction surface / finish: GT Slotted; Black electrocoat
• Ventilation: 60 CV; curved
• Mounting direction: Right-hand
• Preparation: Balanced: yes; factory burnished: no
• Opposite-side component, ordered separately: 160-13790-GTB
• Rotor-to-hat/hub attachment circle: 12 x 10.25 inches
• Attachment hole size or thread: 0.326 inches
• Center registration: 9.64 inches
• Far-side inside diameter: 11.05 inches
• Approximate weight: 24.80 lb
• Quantity: one rotor ring; hat, hub, mounting hardware, calipers and pads are separate

Fitment & Compatibility

Match this 15.50-inch right rotor to the 10.25-inch attachment circle and 9.64-inch register. The 1.38-inch width and 60 curved vanes belong to a specific caliper-and-hat package; pad contact and wheel clearance must be checked on that complete assembly. Hardware is selected for the rotor interface, independently of wheel studs.

Manufacturer reference: Wilwood rotor specifications

For help identifying the correct replacement, share the installed brake package with PMB Performance. Our team draws on over 20 years of experience with brake components and fitment.