Wilwood Rear Red Dynalite/MC4 Conversion, Staggered GM 12-Bolt Axles with 12.19-Inch Drilled Rotors — Selected 1964–1974 Applications

Red Dynalite and MC4 calipers combine hydraulic service braking with mechanical parking action in this staggered-shock rear kit. The drilled-and-slotted rotor assembly measures 12.19 inches and requires the modified GM 12-bolt axle geometry. Wilwood Engineering’s work covers the design and manufacture of disc brake systems for motorsport, street-performance and specialized applications. Bill Wood founded the company in 1977 in a business now based in Camarillo, California. Its calipers, master cylinders, brake rotors, brake lines, valves and fittings must be selected around the complete system.

Technical Details

• Manufacturer: Wilwood
• Manufacturer part number: 140-14259-DR
• Kit classification: Rear Brake Kits - Street Performance
• Axle position: Rear Kits
• Brake Type: Disc; Parking
• Selling unit: Sold as a kit.
• Master Cylinder Included: No
• Brake Booster Included: No
• Brake Lines Included: No
• Rotor Outside Diameter: 12.19 in; 309.63 mm
• Rotor Thickness: 0.81 in; 20.57 mm
• Rotor Material: Iron
• Surface Type: SRP Drilled & Slotted
• Rotor construction: Vented
• Bolt Circle Diameter: 5 X 4.5 in; 5 X 114.3 mm; 5 X 4.75 in; 5 X 120.65 mm; 5 X 5 in; 5 X 127 mm
• Catalog stud / mounting-hole reference: 0.520 in; 13.21 mm
• Rotor surface finish: Black Electro Coat
• Hat material: Aluminum
• Hat finish: Black E-Coat
• Hat offset dimension: 2.000 in
• Pistons per service caliper: 4
• Service-caliper piston construction: Stainless
• Service-caliper mount: Lug
• Caliper body construction: Forged aluminum
• Caliper Color: Red
• Caliper Finish: Red Powder Coat
• Caliper Inlet Port Diameter: 1/8-27 NPT
• Caliper family: Dynalite
• Pad compound: BP-10
• Minimum wheel guidance (clearance drawing required): 15 in; 381 mm
• Required rear axle / flange: 12 Bolt C-Clip Eliminator
• Catalog axle-offset reference: 2.91 in; 73.91 mm
• Spindle Included: No
• Mounting Hardware Included: Yes
• Separate wheel hubs included: No

Fitment & Compatibility

DS-1185 specifies the staggered-shock GM 12-bolt C-clip-eliminator rear arrangement, not a front-spindle conversion. Match the modified housing ends, customer-supplied eliminator bearings, 2.91-inch axle offset and 3.06-inch center registration. Vehicle rows referencing Ridetech spindles do not confirm that rear geometry. Hoses, parking cables and their adapters are separate, and the 15-inch wheel guidance requires a template check.

Listed models: Chevelle; 442; Beaumont; Camaro; Apollo. Use the fitment table below for the individual years, submodels and equipment conditions.

Wilwood product specifications · Installation instructions · Technical bulletin

PMB Performance brings over 20 years of experience to brake-component selection. Provide the actual hardware specification when the brake system has been modified.