Wilwood HV Tandem M/C Kit w L/H Bracket & Prop Valve - 1 1/8in Bore Ball Burnished

Wilwood HV Tandem Master Cylinder Kit 1-1/8in Bore with Proportioning Valve

The Wilwood 261-13270-P packages the Aluminum Tandem Chamber High Volume (HV) Master Cylinder with a combination proportioning valve, mounting bracket, stainless steel fluid tubes, and all hardware. The 1-1/8 in. bore ball-burnished master cylinder is compatible with manual or power brake systems and fits Chrysler, Corvette, GM, and Ford Mustang bolt patterns via its slotted flange. The combo proportioning valve maintains front and rear fluid circuit isolation and simplifies proportioning adjustment on custom brake systems.

Key Features

• 1-1/8 in. bore high volume tandem master cylinder — ball-burnished aluminum housing for smooth pedal response and precision fluid control
• Combination proportioning valve — black e-coated; simplifies brake bias adjustment on custom and race setups
• Slotted flange mount — bolt-on compatible with Chrysler, Corvette, GM, and Ford Mustang OEM mounting patterns
• Full front/rear circuit isolation — combo valve maintains full fluid independence between axles
• Stainless steel fluid tubes — precision bent with pre-installed plated steel tube nuts for direct bolt-on connection
• Stainless steel button-head fasteners — rust-free hardware for long service life
• Compatible with manual or power brake systems

What's Included

• 1x Wilwood 261-13270-P HV Tandem master cylinder (1-1/8 in. bore, ball burnished)
• 1x Combination proportioning valve (black e-coat)
• 1x Mounting bracket (black e-coat)
• Stainless steel fluid tubes (pre-bent with tube nuts)
• Stainless steel button-head mounting hardware

Specifications

Frequently Asked Questions

• Q: What bore size does the 261-13270-P use?
  A: 1-1/8 in. bore. Wilwood also offers this kit in 7/8 in., 15/16 in., and 1.00 in. bore sizes for different pedal ratio and caliper piston area configurations.
• Q: Can this be used with a power brake booster?
  A: Yes. The 261-13270-P is compatible with both manual and power brake system applications.
• Q: What mounting patterns does the slotted flange accept?
  A: Chrysler, Corvette, GM, and Ford Mustang OEM bolt patterns.
• Q: What does the combination proportioning valve do?
  A: It maintains full isolation between front and rear fluid circuits while allowing brake proportioning adjustment, eliminating the need for a separate combination valve in custom brake systems.
• Q: Are the fluid tubes pre-bent?
  A: Yes. The stainless steel tubes are precision-bent and include pre-installed plated steel tube nuts for a direct bolt-on connection between the master cylinder and proportioning valve.
• Q: What is ball burnishing?
  A: Ball burnishing is a machining process that compresses and smooths the bore surface for a precise, consistent finish that provides smooth pedal feel and long seal life.
• Q: Can I adjust the proportioning valve?
  A: Yes. The combination proportioning valve allows adjustment of front-to-rear brake bias, which is critical for custom and race brake systems.
• Q: What is the overall length of the master cylinder?
  A: 8.76 in. overall length.

Installation Instructions

Mount the bracket to the firewall using the appropriate OEM bolt pattern. Attach the master cylinder to the bracket. Connect the combination proportioning valve using the pre-bent stainless steel fluid tubes, torquing the tube nuts to specification. Connect the master cylinder outlet to the proportioning valve inlet. Route the front and rear brake lines from the proportioning valve to the respective caliper and wheel cylinder circuits. Bleed the entire system from the furthest point back to the master cylinder. Confirm full pedal pressure and no fluid leaks before vehicle operation.

WARNING: This product can expose you to chemicals including lead and lead compounds known to the State of California to cause cancer and reproductive harm. For more information go to www.P65Warnings.ca.gov.