Wilwood Left Combination Valve Kit with Bare 15/16-inch Mustang Manual Master Cylinder and Pedal Eyelet

The bare 15/16-inch master uses the early Mustang eyelet pushrod supplied in this kit. Its left-mounted combination valve provides rear-pressure adjustment alongside the tandem cylinder, with the connecting tubes and support hardware included. The manufacturer is Wilwood Engineering of Camarillo, California, established by Bill Wood in 1977. Wilwood designs and manufactures disc brake systems alongside calipers, fittings, master cylinders, rotors, brake lines and valves. Its street-performance, motorsport and specialized ranges require component selection around the demands of the complete assembly.

Technical Details

• Manufacturer part number: 261-14158
• Material: Aluminum
• Cylinder bore: 15/16"
• 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: Bare
• 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

For the matching classic Ford Mustang manual-brake pedal; the associated master family specifies 1964–1972. Confirm the actual pedal, firewall mount and modified brake package, including left-side clearance and adequate stroke before selecting the bore.

Manufacturer Documents

• Wilwood product specifications
• Wilwood DS985 instructions and specifications
• Wilwood FL331 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.