Disc Brakes and Proportioning Valves
In this Tech Tip, John confirms a customer question regarding the need for a proportioning valve on his ’55 F100 brake build.
“I bought one of your disc brake kits several months ago for my 1955 Ford F100 truck. Due to weather and time, unfortunately I have not yet had a chance to install it. My truck currently has power drum brakes. I have a question for you: will I need to add a proportioning valve for your disc brakes?”
Hi, you inquired about a disc brake kit on the front of your ‘55 Ford pickup and the potential need for a proportioning valve. When you install a disc brake kit on the front and everything is plumbed properly you could experience rear wheel lock up if you have to hit the brakes in a hurry. This in turn will not get the full stopping potential out of the front discs. The discs usually take 1200-1300psi as compared to the rear drums taking 600-800psi (depending on the wheel cylinder size). An adjustable proportioning valve such as number 91031353 would be suggested for safer braking. Feel free to visit us on the web at www.speedwaymotors.com or call 1-800-979-0122 with questions or to place an order.
- John W.