Hello everybody i need a little help finding the right master cylinder for my 32 roadster. at the front I install the buick drums with 2 "brake shoes on bendix plates. the original 1940 ford brake is to be used at the rear. i want to use the original pedals without booster. which master cylinder would you recommend? Thanks in advance matthias
I see, then size it the same as a 40 Ford, 3/4 in maybe? I “think” that was the MC bore size on my ‘42 PU. But should be easy to find the information.
You need to know the pedal ratio first. In my experience a 1-1/16 would need a power booster; unless you have a pedal ratio of 7 to 1. 7/8” works good with non power disc/drum. Personally I would use a 3/4 if you can find a dual unit and the ratio is in the 5-1 area. It will have the least pedal pressure but needs more pedal movement than a 7/8” which will work also. With a light car and big front brakes a 3/4” will probably feel like power but it will need the most pedal movement.
Using the original pedals will make getting the proper ratio difficult. Where are you placing the master? If the arm you add to your pedal has to reach under the K member, it will probably be a bit longer than the recommended 6:1 ratio. My 32 sedan has a stock pedal with an added arm that reaches under the K member to the master mounted on the backside of the K, hanging so the rod just clears the K. I used a 1968 Mustang dual master made for a drum/drum manual system. It works OK, but not perfect. The pedal is hard. I have 40 Ford brakes at all the wheels.
Thanks for the answers. I just measured. the pedal ratio is 4/1. But when the pewal path is full, I have 2 "away on the lever - I definitely don't need that! ?? I think more than 1" stroke on the master cylinder is not necessary ?? so i could shorten the lever by half and have a ratio of 8/1. I want to build the MC behind the K-member.
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