Been reading a lot about the pedal ratio, sizes and stroke of the master cylinder, etc. so I can make the brakes work safely. I made a cardboard brake pedal to see how it would all work. Have a 6 to 1 pedal ratio for my manual brakes. 1 inch bore master with a 1 1/16 stroke . So the way it's mocked up, the pushrod moves about 1 1/4 when the pedal is close to the floor. I just want to be sure I'm not missing something, cause this looks like it will fully stroke the master right before the pedal hits the floor . Sound good to you guys ? Any other input or suggestions ? I can't just buy a pedal kit from speedway due to the floor/frame already in place and would be more fab work than making a pedal . Thanks in advance for suggestions.
Just buy a pedal setup from an underfloor brake car. All of the early Studebakers are under the floor. Up to about 1960. Not sure when they went to firewall mount, but it was after 1960. I used a Wilwood master cylinder and put disc brakes on two of my 54 Studes . NO....power assist, works great with the correct piston size master cylinder. Mike
I question the 1 1/16" master cylinder stroke, as most (dual) I've measured are in the 1 1/4"-1 3/8", so #1, make sure you are measuring correctly, and #2, possibly switching to another master, or allowing the pedal to move the push rod longer travel.
Sounds like your on the right track. So many aftermarket pedal assemblies don't work correct. I see so many cars with the pedal in a convoluted area or too low or uncomfortable. And I repeat about the M/C bottoming before the pedal hits the floor. Otherwise your dual M/C wont work if if you have line failure.
Heeeeyyyy I got a concept that no one has even considered, the stock peddle for the car. Ohhhhhhhhhhh The Stude Lowey/hawk was under floor until they went to the Hawk GT in about '63 or 4. The first Avanti was under floor until about '64 too. Not sure about the Lark. Willys/Jeep was under floor until the redesign in 1963. We could go on an on but the bottom line is that there are a lot of underfloor brake peddles out there to choose from and they are not at all hard to come by. I have actually seen a modern redesign of the wheel and guess what they are still round.
Thanks for the input . First, I remeasured the m/c stroke, it's 1 1/8 approx. So I assume a push rod travel of 1 3/8 will be enough ? I truly respect all the input on this board, I should have given a little more info to expect accurate input...the frame is one off built from scratch, the floor in the cab is all new, and very modified from stock. It's a 39 Plymouth pickup hot rod style, no fenders. I'm looking for ways to quit throwing more $ at parts that wind up not working or needling so many changes that I should just build from scratch. Brakes and steering are at the top of my lists for this rod. So, basic question, as long as the pedal bottoms the m/c before it hits the floor, I'm good ???
V8 Bob is right on here. Yes if you run out of master cylinder stroke before you hit the floor you are golden in that respect but you also have to have a master that will work with your brake setup. The bore size of the master is as important as the pedal ratio. One common OEM master that seems pretty universal is the Mustang manual disc drum setup of one if setting up disc drum brakes for instance, or if one is setting up 4 wheel discs I am still real partial to the corvette unit as a starting place. it helps to find the specs on the original setup, like say you have brakes that you know take a 1" diameter ,aster then spec a master that matches that. make sense? Getting back to the peddle ratio, I think that it is 6 or 7:1. My legs are not as good as the last guys so I may lean toward a longer lever for me personally within reason.
I don't think that the brake pedal will work very well if it is under the floor. You won't be able to get your foot on it unless you leave a big access hole It will probably work better with the pedal above the floor and the M/C under the floor
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