I am refurbishing a 1985 Mustang GT that was used in the SCCA American Sedan class from 1990-95. It is a gutted, "climb in the window" race car. I've not raced it in the Vintage events yet. I have used it for about 400 miles on the street (cruise nights). It has NJ Collector Car inspection and plates and is limited mileage street legal.
The front brakes are the OEM FoMoCo and the rear disc brakes are (seller told me) a Ford Racing conversion kit. The Master cylinder appear to have been replaced and may have been part of the rear disc brake conversion kit. The proportioning valve appears to the the OEM 1985 (disc/drum) but I am not positive it is.
The front brakes "drag" or stick after the car is driven and warms up completely. This problem existed as soon as I got car on the road. I found and replaced a frozen RF caliper thinkng the problem was cured. I replaced both front calipers w/rebuilt units at that time.
When the car is cold, the front wheels spin freely as do the rears. Only after the car warms up does the problem arise. I drove 10 highway miles yesterday directly to a garage with a lift, raised the car and both front wheels could not be turned by hand. After letting the car cool down for an hour, the front wheels spun freely again! The rear brakes never stick and always spin freely.
This problem is so bad that from 20 mph down to 0 (while coasting), the car will stop itself as if a ghost was stepping on the brake pedal!
Could header heat on the stock location proportioning valve be causing this? Could the proportioning valve be for disc/drum and not the right one for 4 wheel disc brakes? Could the proportioning valve be defective?
The brake fluid is clear as bottled spring water and nothing is leaking. Although I plan on eventually replacing the proportioning valve with a brake bias valve, I'd like to fix this problem first. Keep in mind that I'm assuming the valve is the culprit. Any ideas would be apprectiated.
Thanks
The front brakes are the OEM FoMoCo and the rear disc brakes are (seller told me) a Ford Racing conversion kit. The Master cylinder appear to have been replaced and may have been part of the rear disc brake conversion kit. The proportioning valve appears to the the OEM 1985 (disc/drum) but I am not positive it is.
The front brakes "drag" or stick after the car is driven and warms up completely. This problem existed as soon as I got car on the road. I found and replaced a frozen RF caliper thinkng the problem was cured. I replaced both front calipers w/rebuilt units at that time.
When the car is cold, the front wheels spin freely as do the rears. Only after the car warms up does the problem arise. I drove 10 highway miles yesterday directly to a garage with a lift, raised the car and both front wheels could not be turned by hand. After letting the car cool down for an hour, the front wheels spun freely again! The rear brakes never stick and always spin freely.
This problem is so bad that from 20 mph down to 0 (while coasting), the car will stop itself as if a ghost was stepping on the brake pedal!
Could header heat on the stock location proportioning valve be causing this? Could the proportioning valve be for disc/drum and not the right one for 4 wheel disc brakes? Could the proportioning valve be defective?
The brake fluid is clear as bottled spring water and nothing is leaking. Although I plan on eventually replacing the proportioning valve with a brake bias valve, I'd like to fix this problem first. Keep in mind that I'm assuming the valve is the culprit. Any ideas would be apprectiated.
Thanks