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Product details
A 15/16-inch tandem bore and right-mounted valve define this black Mustang package. The manual pushrod must connect to the specified pedal without altering the master cylinder's required free play or travel. Bill Wood's founding of Wilwood Engineering in 1977 established a disc brake design and manufacturing business based in Camarillo, California. Calipers, rotors, master cylinders, fittings, valves and brake lines form its range for motorsport, street-performance and specialized applications. Choosing a service component still requires checking the mating parts and overall system configuration.
Technical Details
- Manufacturer part number: 261-15664-BK
- Material: Aluminum
- Cylinder bore: 15/16"
- 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, right-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 classic Mustang application against the actual pedal and firewall flange. Confirm the chosen bore for the installed calipers and pedal ratio.
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
PMB Performance has more than 20 years of experience matching brake components. Share the actual mounting, linkage and hydraulic arrangement when requesting fitment assistance.
