I'm replacing the stock single chamber master cylinder on my '41 Buick with a dual chamber MC. They are both 1" bore and I've machined the OEM push rod to work with the new MC. When the brake pedal is completely returned to when it's flat on the floor the push rod has 1-1/4" of travel. The piston on the original MC has a 1-1/2" stroke until it's completely bottomed out. The new MC has about 1-1/8" stroke until it bottoms out, which means when I set up the push rod with about 1/8" of play before it actuates the piston, the piston bottoms out at the same time as the pedal hitting the floor. Is that ok, or should the new MC have a longer stroke? I'm sure if the brake system is set up properly that piston never hits bottom, but since the stock system was set up so that the pedal was on the floor before that piston bottomed out I wanted to make sure the shorter stroke on the new MC wasn't going to be a problem. Thanks for the input. Curt
Should be fine, you are correct, the piston will never bottom out. Unless you run out of brake fluid! Just be sure the pedal can travel as far as it needs to, when you put the insulation/carpeting in the car. I had TONS of trouble gettting late model brakes to work on a 34 Terraplane I did. Usually the rod will travel 3/4 to 7/8" and develop full pressure in the lines (800-1200 PSI). Love that Buick, any idea when she'll be done?
Hey man! Thanks for the info. I'm chipping away at the Buick a little more each winter then having fun with it during the summer. If all goes well I'll at least have some more holes filled, the headlights frenched, and the skirts and flipper caps fitted up by the Jalopy Showdown. Mildly chopped top, interior, etc. Is still down the road. I'm planning to drive it to Gettysburg...are you going this year?
Nah, I haven't been to G'burg since the KKOA left there. Just have a bad taste in my mouth about it, so to speak. Another group "stealing" the name, date, grounds of an older existing show. Yeah. I'm probably being a bit of a jerk about it. Got so much going on building stuff, I rarely take time to go out and have fun any more. Maybe when my 46 Chevy's done.....
Me neither...in fact the last time I went was when you brought the Kart down. There was nothing cooler than seeing that thing buzz across the field when you guys got there!
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