brake booster mounting

[harbourmicah]

i just got a brake booster and master cylinder from cpp. has anyone heard or seen a truck that has mounted this without the brackets on the back of the booster? as in mounting the booster to the firewall. i saw this on a blue 70's blazer at the goodguys show at texas motorspeedway in october and thought it looked alot more clean than with the brackets. anyone got some input?

[badriand]

Kinda confused, with or without brackets it still mounts to the firewall i would think. You mean maybe they cut the brackets off and mounted it from the inside or something? Got a pic?

[badriand]

You mean like this one? The actual booster mounts from the inside of the truck against the firewall instead of the outside. The mounting holes are on each side of the pushrod.

[harbourmicah]

yes like that one but i want to know what all goes into installing it this way.

[harbourmicah]

is that off of the cpp website?

[badriand]

No , that was on a 50 something ford truck. Can't remember the site, looked it up at work. Dunno you will have to check around and see what boosters will mount on the inside and work with your truck. The one you have is pretty easy to install, if you get another you might have to do some different modding to make it work. Maybe bore the hole out for the pushrod and shorten the pushrod. Hard to say without looking at one.

[badriand]

harbourmicah , looks like you access to some nice tools and shop. I've got some friends that live in Frisco and little Elm.

[protrash64]

This is good question.....I have seen the same thing. The booster on the firewall. With the brackets on the booster the whole thing is competing w/ the fan shroud! I wonder if people have used the "generic" booster set-ups that require the pedal brcket and so forth. Even the hydroboost systems mount dirctly to the firewall.

[badriand]

harbourmicah, if that is your yellow truck i can understand trying to clean it up a bit but on a truck like mine no worries. I got to throw a ugly spot someone else to help take attention off the other ugly's.

[harbourmicah]

yes most of those pics are at my high school auto body shop. the others are in my garage.

but to the question at hand, i have come to the conclusion that all i would need is a shorter pushrod if i were to do this. i called cpp and they said i shouldnt do this because it would change the angle of the stroke the pushrod made. how important is it to have the pushrod go straight in and out? anybody have some experience with it? i just dont want to end up tearing up these brand new parts.

[badriand]

Important enough to if you stop or not. If it is at an angle and it doesn't push that rod enough into the booster then it may or may not cause the booster to charge thus your stopping is weaker. May work for a while then your moving pretty good and it doesn't work, you may not stop as quick as you like. If your moving up 75 or plano prkwy stopping has to be an option. CPP knows there stuff. If your determind to go the other route maybe you can make the hole for the firewall a little bigger and slide the booster down or up making the angle more of a straight shot. Maybe there are some other guys on here that have done it , have to wait and see. Mine is mounted at an angle but i guess when you press the pedal it needs to go forward straight in the same angle.

[PrerunnerRob]

Originally Posted by harbourmicah

yes most of those pics are at my high school auto body shop. the others are in my garage.

but to the question at hand, i have come to the conclusion that all i would need is a shorter pushrod if i were to do this. i called cpp and they said i shouldnt do this because it would change the angle of the stroke the pushrod made. how important is it to have the pushrod go straight in and out? anybody have some experience with it? i just dont want to end up tearing up these brand new parts.

It's pretty important, you don't want to side load the piston at all if possible. It would be higly unlikely, but the piston could cock sideways in the bore and get stuck. What about moving the pivot point on the pedal to maintain a strait in and out angle?

[harbourmicah]

i think i will do so, if i get a shorter rod, relocate the mounting of the rod on the brake pedal so that it goes straight in and out, i should have no problems unless i am forgeting about another factor. anyone have something else to add?

[Brad54]

Two weekends ago I pulled an original power booster off of a '65 in a junk yard. It mounted flush to the firewall, with the studs on the booster going through the firewall, and nuts on the back side holding it in place.

Just some random things to think about: from the factory, a lot of '50s and '60s vehicles had bolts running from the back of the brake pedal assembly through the firewall, with the nuts on the engine-bay side of the firewall. In some of these applications (such as my '56 and '57 Chevy cars), two of those studs are what the manual master cylinder bolted to.

Most retro-fit power booster kits use those brackets because they need to mount a power booster to the firewall where there are either no existing holes for the booster, or the brake sled mounts with studs sticking through the fire wall, and the booster has studs going through the firewall from the other direction.

I can't see a reason you can't mount the booster flush to the firewall; Locate the holes in the firewall, and make sure the rod is the right length, and travels in a straight line. NOTE: With power brakes, it is typical for the location of the rod on the brake pedal to be moved up, towards the dash, about 3/4 of an inch to change the pedal/effort ratio. I don't know why, but that seems to be SOP.

-Brad

[Tomsriv]

I have a setup from CPP as well. I mounted it to the firewall on the engine side. It is designed to use 4 holes instead of the stock two. I had to drill 2 holes, pull off the brake pedal and get everything adjusted. It took me a whole day to do it.