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Hydroboost Installation question

ksagis

Contributor
Aspiring Bronco Guru
Joined
Jun 15, 2020
Messages
292
James,
To answer your original question: Pedal travel goes from is 6.5 to 5 inches from floor.

Ebay short bracket, modified to ratio of 1.26 (see post #87)
Cardone 52-7333 (95 AstroVan HB)
Raybestos MC36306 (80 Camaro 1-1/8" piston MC)
77 D44 front disc
71 BB rear drum

View attachment 932608
Oldtimer, looks good! Wish I could bend brake lines as nice as you.

Wanted to check, are you saying the pedal height when not pressing the brakes is 6.5” and when the brakes are applied, the pedal height is 5”? (1.5 inches of pedal travel).

If I have that right, thats a good spot to be.

P.S. That doesn’t look like a Vette MC to me since they have disk/disk and two same size pots. I think 1980 Vette is MC39052?

https://www.rockauto.com/en/catalog...041152,brake+&+wheel+hub,master+cylinder,1836
 
Last edited:

Oldtimer

Contributor
Jr. Member with Sr. moments
Joined
Feb 4, 2005
Messages
1,038
Loc.
Sunnyvale, CA
Yes, pedal height at rest is 6.5 inches off floor, and 1.5 inches of total pedal travel, but brakes are locked up after about 1/2 inch of travel.

A Ridgid 403 tube bender makes it look easy, and copper nickle brake line is very forgiving.
 

catfan

Full Member
Joined
Jul 1, 2016
Messages
278
Here is a mock up of mine , I left the bottom off so you could see it.
 

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ksagis

Contributor
Aspiring Bronco Guru
Joined
Jun 15, 2020
Messages
292
Yes, pedal height at rest is 6.5 inches off floor, and 1.5 inches of total pedal travel, but brakes are locked up after about 1/2 inch of travel.

A Ridgid 403 tube bender makes it look easy, and copper nickle brake line is very forgiving.
Sounds like it turned out great!

This is where I believe the reduction in pedal ratio either at the bell crank or the pedal is key. With brakes locking up at 1/2”, reducing the mechanical advantage helps with pedal feel.

Out of curiousity, what size tires and wheels do you have? (wondering about rotating mass)
 

ksagis

Contributor
Aspiring Bronco Guru
Joined
Jun 15, 2020
Messages
292
Here is a mock up of mine , I left the bottom off so you could see it.
Looks like the angle on pushrod on bellcrank to hydro is nearly 90 degrees and if other is also close to 90 then the ratio is same as ratios of lever arms. Looks great to me.
 
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