Wilwood One-Inch Compact Master Cylinder Kit with Direct-Mount Billet Reservoir, Black Body

The one-inch single-outlet compact master is supplied with a direct-mounted aluminum reservoir. A 2.25-inch vertical flange and threaded pushrod connect it to the matched pedal arrangement. Master cylinders are part of Wilwood Engineering's wider disc brake range, alongside calipers, rotors, valves, fittings and brake lines. Wilwood was founded in 1977 by Bill Wood and designs and manufactures its systems from Camarillo, California for motorsport, specialized and street-performance applications. Hydraulic sizing and mechanical compatibility remain decisions for the complete brake system.

Technical Details

• Manufacturer part number: 261-16840-1.00
• Material: Aluminum master body and billet aluminum reservoir
• Cylinder bore: 1.00"
• Pressure circuits: 1
• Stroke Length: 1.12 in
• Listed displacement per stroke: 0.87 cu in
• Reservoir Type: Direct-mounted reservoir on Compact Remote cylinder
• Fluid capacity: 4.00 oz
• Flange-to-end length: 3.37"
• Overall Length: 7.80"
• Mounting centers: 2.25"
• Pushrod dimensions: 4.00" x 5/16-24
• Finish: Black E-coat
• Inlet arrangement: 0.87-inch seating diameter with 11/16-20 internal thread; this is the reservoir feed, not the pressure outlet
• Pressure connection: 1/8-27 NPT outlet; select the appropriate pressure-line adapter
• Reservoir package: One directly mounted 4 oz Type III hard-anodized finned billet reservoir with cap and seals

Fitment & Compatibility

Verify bore selection, pushrod engagement and full piston movement. Confirm that the body-mounted reservoir clears nearby structure and remains serviceable.

Manufacturer Documents

• Wilwood product specifications
• Wilwood FL554 instructions and specifications
• Wilwood FL162 instructions and specifications

PMB Performance offers over 20 years of parts and brake-fitment experience. For a compatibility check, provide the existing assembly and the dimensions that govern the replacement.