Wilwood Black One-Inch Mustang Tandem Master Kit, Manual Pushrod and Left Valve Mount

This one-inch compact tandem kit includes the Mustang manual-pedal pushrod, distinguishing it from a same-bore master supplied for separate booster actuation. The valve mounts on the left of the black master body. Wilwood Engineering began in 1977 under founder Bill Wood and is based in Camarillo, California. The company designs and builds disc brake systems for motorsport, street-performance and specialized applications, with a range extending through calipers, rotors, valves, brake lines, fittings and master cylinders. Individual parts must be compatible with the system in which they operate.

Technical Details

• Manufacturer part number: 261-15544-BK
• Material: Aluminum
• Cylinder bore: 1.00"
• Pressure circuits: 2
• Stroke Length: 1.10 in
• Reservoir Type: Integral tandem chambers, 7.8 and 4.7 oz
• Fluid capacity: 7.8 / 4.7 oz
• Flange-to-end length: 6.55"
• Overall Length: 12.32"
• 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
• Kit contents: Master cylinder, left-side combination proportioning valve and bracket, formed stainless connecting tubes and mounting hardware
• Combination-valve functions: Adjustable rear pressure, isolated front/rear circuits, front-line junction and hydraulic brake-light switch

Fitment & Compatibility

Check the documented classic Mustang pedal geometry and flange. A one-inch bore must be selected with the calipers, pedal leverage and required fluid travel.

Wilwood’s kit summary gives a 1964–1973 Ford/Mustang range, while the corresponding bare-master family identifies 1964–1972. Confirm the actual manual pedal, supplied eyelet and mounting geometry, particularly for 1973, before ordering.

Manufacturer Documents

• Wilwood product specifications
• Wilwood FL162 instructions and specifications
• Wilwood DS1287 instructions and specifications
• Wilwood DS1178 instructions and specifications
• Wilwood FL311 instructions and specifications

With more than 20 years of experience, PMB Performance can help compare the specified part with the assembly you are servicing. Include the existing part identification and relevant hydraulic dimensions.