Sweeting Performance - Bosch Hydro-Boost, Bosch Hydro-Max, Vacuum, and Air-Hydraulic Power Brake Systems
Wilwood Single Adjustable Proportioning Valve, Knob Type
Product Description
Adjustable rear proportioning valve with pipe thread adapter to common 3/8 brake fitting.
NSTALLATION & ADJUSTMENTS - Proportioning valves are normally installed in the rear fluid line to prevent the rear wheels from locking before the front wheels, or to give a driver the ability to make fine adjustments in front to rear bias percentage on the track to compensate for tire wear, fuel load burn-off, or changing track conditions. It is generally not recommended to attempt to reduce front wheel braking capacity.
Use only the two .25" body holes to secure the valve to a mount. Do not attempt to remove the adjuster knob or valve body end cap to facilitate thru-panel mounting.
Two 1/8-27 NPT to 3/8-24 inverted flare fittings are supplied to adapt double flared hard brake lines to the valve. Connect the "IN" port to the pressure line coming from the master cylinder. Connect the line going to the calipers to the "OUT" port.
The adjusting knob is marked with an arrow indicating the direction required to decrease line pressure to the calipers. The knob rotated all the way out (counter-clockwise) will provide a maximum pressure reduction of 57%. Rotating the know in (clockwise) will incrementally increase line prressure, up to full pressure. If the range of adjustment in the valve is not sufficient to properly balance the vehicle’s bias, changes to other components within the system may be necessary.
TESTING THE SYSTEM - Do not attempt to operate the vehicle until the system has been fully tested under controlled conditions in a safe location. After the system has been bled, checked for leaks, and the proper pedal resistance and travel have been determined, make a series of low speed stops, then gradually progress to normal operating speeds.
WARNING - Adjustable proportioning valves are designed for tuning and balancing custom brake systems on performance, racing, and other types of special purpose vehicles. They are not designed as direct replacements for any OEM application.
Accessories