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Discussion Starter · #1 ·
Have a booster from Speedway, need to remote mount it. The question being "how long is the input shaft stroke from full out to fully in" ? I need to make a drop in the connector shaft from the floor mounted pedal to the booster to clear the trans mount and attach the end to the threaded booster shaft. I am concerned with how much of the shaft end I can use without interference. Is my question even understandable? I can't push the shaft in by hand as it isn't hooked up and, I assume, I need vacuum.
 

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booster

You can move the booster back to in front of the rear wheel with a rod running from the pedal to the booster. You did that already. Two things, first the pedal ratio and travel will answer your question about how far the rod should travel. To say it another way, an aftermarket pedal with a ratio of, say 6:1 that normally was hooked almost directly to the booster (pedal, booster, M/C set)will have the same travel when the booster is relocated further back, just a longer rod. Second is the rod itself. You must have a stout rod to prevent ANY flex. Hope this helps. Oh, and even if you have to put a bend in the rod it still will have the same travel.
 

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Discussion Starter · #4 ·
O K...the booster has a threaded rod, with a nut,extending from the booster. How much does that rod move into the booster? ! inch ? Two inches? Inch and a quarter? If I know how far into the booster...I will know how much of that rod I can use to attach my brake pedal connector rod. The booster has never been on a car and I don't even know how they are NORMALLY hooked-up. With the booster on the bench, I cannot push the rod into the booster by hand to measure the travel.I assume because there ain't no vacuum yet.Is my reply as muddled as the question?
 

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Booster

The threaded rod is used to adjust the pedal free play. As a starting point use about half the threads and see where the the pedal free play stops. The free play should be about 1" or so before you start to feel resistance as the rod starts to push the diaphragm. As a side note don't push the brake pedal on a new, dry master cylinder. There would be a good chance the front piston will stick down.
 

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Most of the master cylinders I've seen had between 1" and 1 1/8" of piston stroke. I guess that's what you're asking?

Russ
 

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Booster

Nope, not asking anything, trying to tell you about rod travel. The 1" and 1 1/8" thing is the M/C bore size and has nothing to do with rod travel. You need to do research on M/C, boosters and brakes in general.
 

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Thought this picture from a Hotrod shop over here might help to show how to mount a remote booster. As you can see the pedal does not have to be in direct alignment with the booster due to the spherical bearing rod end on the pedal rod. You would need the same type of rod end at the pedal arm. You could take the master cylinder off of the booster, put a little bit of brake fluid in it to lubricate it then push the piston in to find out the amount of travel.
 

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Gotta love a turbo!
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Nope, not asking anything, trying to tell you about rod travel. The 1" and 1 1/8" thing is the M/C bore size and has nothing to do with rod travel. You need to do research on M/C, boosters and brakes in general.
Ahh, no. That's the travel of the stroke going from full out to full in. Look again, my post plainly states stroke. Check any automotive M/C you find, the stroke is all about the same...

Russ
 
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