1967-1968-1969 FORD MUSTANG MERCURY COUGAR 9" ZINC BOOSTER MASTER CYLINDER KIT




This listing is for a Brand New 9" single diaphragm ZINC power brake booster with Bail Top Master Cylinder and Disc/Drum Proportioning Valve Kit for 1967 1968 1969 Ford Mustang, Fairlane, or Mercury Cougar with disc brakes in front and drum brakes in rear.

Additionally this includes a Brand New Zinc Bail top master cylinder. This master cylinder is the Bail Top Style & has a 1" Bore. Mounting holes measure 3 3/8" center to center.  This is a four port master cylinder, so you can use the ports on whichever side you need and block the others. It includes plugs for the ports you do not use. This is a great upgrade over a standard GM style master.

Also included is a DISC/DRUM proportioning valve kit (self adjusting valve  and bracket to mount kit to the side of the master cylinder).

The proportioning valve has a zinc finish.  This valve is also call a combination valve, as it performs all of the necessary valving functions with a disc brake conversion.  These functions include the following:

  • Proportioning:

As more force is applied to the brakes and the car begins to lean forward, less braking force is needed in the rear.  This valve decreases the pressure to the rear, preventing lock up.

  • Metering:

Metering is used in the front disk brake portion in the disc/drum system to delay application of the front discs allowing the slower reacting drum brakes to catch up.  This provides rear stability on wet surfaces and helps prevent front pad wear.  There is no metering function with the disc/disc setup.

  • Residual Pressure:

Drum Brakes require residual pressure of 10 lbs. to be held in the line.  This pressure keeps the brake shoes close to the drums giving you a more firm pedal feel.  The disc/disc setup does not require this pressure.

  • System Failure Switch:

This valve has a system failure switch that will alert you when half of your braking system is not working properly.


7901Z + 3511 + PV2 Side Mount Kit (19#)




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