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Discussion Starter · #1 ·
Hi folks I have a 1964 F100 hotrod with power brakes - but it uses a very high leverage mounting location for the pushrod probably for manual brakes. The travel of the pushrod is extremely short as you can see in the video (link below). My real problem is that the brake pedal sits a good 6" higher than the gas pedal. It may be right for the truck but I need to change it. I'm considering tilting the booster GM style - or even switching to a tilted GM booster like CPP sells to lower the pushrod mounting point and pull the pedal to towards the floor. Looking for ideas or anyone with experience modifying brake pedal travel

Current pedal position - really HATE this:
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Current Pushrod mount position - very high for high leverage
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Current booster setup (level)

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Youtube video showing short pushrod throw >>>>>>>>> High leverage position

GM style tilted:
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Master cylinder/boosters are not good looking but tilted M/C boosters are just plain ugly (I think). What is your pedal ratio? Though about extending the pedal arm? Last resort would be to relocate the entire unit to under the floor. Extending your arm will change the ratio and should not go more than 6:1. A new design of the pedal with a different pedal rod attachment point may solve the problem and keep the ratio around 6:1.
 

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Discussion Starter · #3 ·
I'm assuming I have to keep the rod perpendicular which is why I was thinking tilt. I'm fine discarding the whole pedal assembly - its entirely separate from the gas pedal anyway. So an aftermarket setup is fine. But with the booster that high up on the firewall and being that flat - what are my options?
 

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Well.
You could go 90 degrees and have it behind the dash.

Good chance your talking a smaller booster or hydroboost to even come close to it fitting. Remote fill of course.

Not a cheap, easy, or convenient option. But still an option.
 

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Discussion Starter · #5 ·
So here is what I'm thinking now. I'm going to try a few things.
  • Going to plan to move the pushrod down an inch from the current mount point on the pedal. That should give me more stroke on the pushrod and less pedal travel. It will also pull the pedal towards the floor
  • If I have a gap to the floor after that I'm going to slice the pedal arm below the brake light switch, bend it and re weld.
  • If necessary I'll slightly shim the booster bracket in the engine bay to compensate if there is any binding.
 

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Discussion Starter · #6 ·
I think I found a really elegant solution for all this. Mopar B Body brake pedal bellcrank. I would need to make a mount for it against the firewall in the cabin but otherwise it looks like it will bolt right up without messing with anything else. I'd go from 6:1 manual setup to something approximating 4:1
Here is the mopar setup and the part being sold by YearOne.
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Looks like a good solution, I did not know that existed. Are you going to use the entire Mopar pedal assembly or just the bellcrank? It appears to me that the bellcrank will cut your pedal ratio in half, do you see it that way?
 

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Discussion Starter · #8 ·
Looks like a good solution, I did not know that existed. Are you going to use the entire Mopar pedal assembly or just the bellcrank? It appears to me that the bellcrank will cut your pedal ratio in half, do you see it that way?
I guess it depends on how far down the pedal I go with the drilled hole. I don't have to keep the bellcrank arm 100% perpendicular, I could just try a hole ~1" down, which might create a drastic angle for the bellcrank's "pedal arm" but also notice I could drill a hole in the bellcrank itself and move the "pedal arm" up the bellcrank to restore some leverage (and perpendicularity if that's a word) if necessary. Flexible approach I think.
 

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Discussion Starter · #9 ·
So I have a second pedal assembly so its easy to compare to the Dodge design. The Dodge's master pushrod is virtually level with the pedal pivot and the Ford's master pushrod is down the pedal maybe 1.5" or so. So to your point about leverage I need to keep the bellcrank "pedal arm" pivot point pretty high up on the bellcrank to have reasonable leverage. So yeah I'll have to drill it and move that arm up.

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