Wilwood Power-Brake Tandem Master Cylinder, Bare 1-1/8-inch High Volume Body

The 1-1/8-inch High Volume Tandem master is intended primarily for vacuum- or hydraulically assisted brake systems. Its bare aluminum housing carries the reservoir above the bore, with access to the two circuits from either side. Wilwood Engineering designs disc brake systems and manufactures a range of calipers, master cylinders, valves, fittings, rotors and brake lines. Founded in 1977 by Bill Wood, the Camarillo, California company serves specialized, street-performance and motorsport applications. Component selection requires understanding the brake assembly as a whole, including its hydraulic sizing and mechanical interfaces.

Technical Details

• Manufacturer part number: 260-8556
• Material: Aluminum
• Cylinder bore: 1-1/8"
• 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: 8.76"
• Mounting centers: 3.22–3.40"
• 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

Fitment & Compatibility

Check booster output, engagement depth and displacement requirements before choosing this larger bore. The mounting flange spans 3.22–3.40 inches; a separate compatible pushrod or booster connection must provide full travel and complete return.

Manufacturer Documents

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

For help choosing the correct service or conversion component, contact PMB Performance with the existing brake-system details. Our team has over 20 years of experience working through parts and fitment requirements.