What Master Cylinder for dual piston disc brake conversion?
Posted: December 17, 2016, 12:22 am
We have transplanted the entire front suspension from a heavy axle 1979 F-250 into a 1966 F-250. The heavy axles use the double piston brake calipers and I need a part number for a manual (not vacuum power boost) master cylinder.
I have done a couple of conversions on 1965 F-100s and used the Raybestos MC39469 manual master cylinder with good results on the single piston calipers on the F-100. This master cylinder has a 1 inch bore and works fine with the single piston calipers. The power brake master cylinder for the dual piston appliction, Raybestos MC36352 lists a 1 1/4 inch bore. Do I need a manual master cylinder with a larger bore than 1 inch to adequately power the dual piston calipers or is the larger size due to the vacuum booster application. Comparing the single and double piston calipers the surface area of the caliper pistons seem to be pretty close since the diameter of the single piston is much larger than the diameter of each of the double pistons on the double piston caliper. The Raybestos tech line will not give any information on non stock installations due to liability concerns. All thoughts and experiences will be greatly appreciated and a part number would be outstanding.
I have done a couple of conversions on 1965 F-100s and used the Raybestos MC39469 manual master cylinder with good results on the single piston calipers on the F-100. This master cylinder has a 1 inch bore and works fine with the single piston calipers. The power brake master cylinder for the dual piston appliction, Raybestos MC36352 lists a 1 1/4 inch bore. Do I need a manual master cylinder with a larger bore than 1 inch to adequately power the dual piston calipers or is the larger size due to the vacuum booster application. Comparing the single and double piston calipers the surface area of the caliper pistons seem to be pretty close since the diameter of the single piston is much larger than the diameter of each of the double pistons on the double piston caliper. The Raybestos tech line will not give any information on non stock installations due to liability concerns. All thoughts and experiences will be greatly appreciated and a part number would be outstanding.