• Allows adjusting the hydraulic pressure to the rear brakes.
• Adjusting the rear line pressure alters the force applied by the rear brakes.
• Allows adjusting the rear brake torque to better balance the rear brakes with the front brakes.
• Extremely helpful when swapping brakes from one model/year to another.

• Designed and manufactured by Wilwood.
• Has standard SAE threaded ports.
• Direct fit for inverted flare brake lines with 3/8-24 tube nuts.
• Direct fit in rear brake line of 1983-1993 Mustang: No adapters needed.
• Rotating the knob makes the pressure adjustment.
• Provides infinite adjustment increments.

Fits

• Direct bolt-in fitment to 1983-1993 Mustang.
• Ports fit 3/8-24 inverted flare tube nuts.
• Fitment for other Mustang years requires adapter fittings or cutting and flaring of the rear brake hard line.

Do you have a 1994-2004 Mustang?
Use the BPV-3 proportioning valve.

Why would I want to adjust brake bias?

Adjusting the brake balance is usually necessary whenever the brake system is changed significantly, such as by swapping calipers and/or rotors from a different year/model Mustang, or converting to manual brakes. Even modifications such as a stiffer suspension and sticky tires can alter how much rear brake bias a particular car can utilize. Installing a Wilwood Adjustable Brake Proportioning Valve allows you to fine-tune your Mustang's brake balance to optimize the brake bias to match your car's setup.

How does an adjustable valve work?

An adjustable proportioning valve changes the front to rear brake balance by reducing the hydraulic line pressure to the rear brakes, whenever the inlet pressure is above the breakpoint pressure set by the valve adjustment. Below the breakpoint pressure, the rear line pressure will always be the same as the front pressure. Above the breakpoint pressure, the rear line pressure will always be less than the front pressure.

How is the valve installed?

The proportioning valve itself may be mounted in any physical location; it simply needs to be plumbed into the proper line of the brake system. The valve is always placed in the rear brake line, between the master cylinder and the rear brakes, or between the master cylinder and ABS unit on cars with ABS. Depending on the model year, installation may be an easy task, or it may require some ingenuity to accomplish.

The BPV-1 valve comes with the correct 3/8-24 inverted flare fittings for a very easy installation on a 1983-93 Mustang. These model years have a splice-block in the rear brake line, located on the passenger side of the firewall. The adjustable valve can be easily plumbed into the system at that point. The valve may be located there, or additional hard-lines can be used to reach the valve if it is mounted elsewhere.

How do I remove or disable the stock brake proportioning valve?
There are two ways to do so:

1. Remove the stock valve with MM's Brake Proportioning Valve Eliminator Kit.
2. Disable the stock valve by removing the internals and replacing the stock valve's plug with the MM-2450-A solid plug.