Wilwood Black Seven-Eighths Tandem Master Cylinder for 1964–1972 Ford Mustang Manual Brakes

The black E-coated version pairs an early-Mustang manual pushrod with a seven-eighths-inch tandem master. Pressure can be taken from either side of the cylinder using the supplied line adapters, with the unused ports closed by the included plugs. Wilwood Engineering, the Camarillo, California disc brake manufacturer founded by Bill Wood in 1977, designs and builds systems for specialized, motorsport and street-performance applications. The product range covers brake lines, valves, fittings, calipers, master cylinders and rotors. A replacement component must preserve the intended relationship between the system's hydraulic and mechanical parts.

Technical Details

• Manufacturer part number: 260-12900-BK
• Material: Aluminum
• Cylinder bore: 7/8"
• Pressure circuits: 2
• Stroke Length: 1.10 in
• Reservoir Type: Integral
• Fluid capacity: 8.0 / 4.8 oz
• Flange-to-end length: 8.15"
• Overall Length: 13.65"
• Mounting centers: 3.22–3.40"
• Pushrod dimensions: 5.75"
• Finish: Black E-coat
• Native pressure ports: 1/2-20 at both circuits; use the correct included outlet adapters and seal washers
• Circuit outlet adapters: Primary: 3/8-24 or 1/2-20 inverted flare; secondary: 3/8-24 or 9/16-18 inverted flare
• Hydraulic relationship: Equal pressure output from the two circuits before external proportioning; 2:1 primary/secondary volume relationship
• Service: Factory rebuild only; do not disassemble the tandem piston assembly

Fitment & Compatibility

Confirm the 1964–1972 Ford Mustang manual pedal, mounting flange and brake-system displacement before installing. The two reservoirs feed separate circuits, and their routing must follow the manufacturer's primary/secondary instructions. Allow complete pushrod return and the full 1.10-inch travel before the pedal reaches any stop.

Manufacturer Documents

• Wilwood product specifications
• Wilwood DS969 instructions and specifications
• Wilwood FL162 instructions and specifications
• Wilwood DS487 instructions and specifications

PMB Performance brings over 20 years of brake-system experience to component selection. Send the installed cylinder, pedal and connection details if you need help checking this configuration.