Register now to get rid of these ads!

Technical Firewall Mounted Brake Pedal

Discussion in 'The Hokey Ass Message Board' started by Century, Apr 16, 2014.

  1. Century
    Joined: May 28, 2009
    Posts: 176


    Hi all,

    I'm looking for a compact firewall mounted swing pedal that I can find in a junkyard. I'm currently working on a dual MC conversion for my '56 Buick and would like to gather all the parts before starting anything. I intend to use a late 60's/70's GM master/booster setup (readily available on RockAuto for $100-130), and I'm looking for something that will work with that.

    I've noticed some of the late model Jeeps and Fords have very compact units. From my understanding, GM uses a 3-3/8" bolt pattern for its 4-bolt boosters - is this something that is standard across the board? I'm wondering if a late model Chrysler/Ford pedal will bolt up to a GM booster.

  2. squirrel
    Joined: Sep 23, 2004
    Posts: 48,277


    78-87 GM midsize pedal assembly is pretty compact, you will probably need to brace the firewall, as I recall it does not have a bracket to go to the dash, although adding one would probably give the strength it needs. The pedal is kind of modern ugly though. For a more appropriate pedal, look for something from 55-64 on a Chevy or other GM.
  3. 1971BB427
    Joined: Mar 6, 2010
    Posts: 6,670

    from Oregon

    Check out late 80's-90's Subaru Legacy pedal assembly. Only about $20 at the pick n pulls, and deigned for a flat firewall. I have one in my Austin gasser, and they're extremely compact.
  4. Century
    Joined: May 28, 2009
    Posts: 176


    Thanks for the tips. Anything else I can look out for at the junkyard? Perhaps something I can use the booster/master out of as well (disc/drum)?

  5. Century
    Joined: May 28, 2009
    Posts: 176


    Bumping this up - heading to the yard this weekend, any tips appreciated.
  6. You have a big car, so think of a bigger donor car, like an old Impala, Belair. I'd think that something from a '65-70 would be pretty good. I've seen pedal assemblies offered as new items too.
  7. porky55
    Joined: Aug 23, 2013
    Posts: 269


    I've heard 80's cameros have good donor pedals. I've also heard good things about jeeps

    Posted using the Full Custom H.A.M.B. App!
  8. Most 70's pedal assy's ARE fair compact, given as they run only from the firewall to the dash. The pedal ratio is what you need to remain, all else is somewhat flexible.

    However, you MUST brace the firewall, and it is an extremely good idea to attach to the dash as factory. I have, in the past, run angle along the side of the assy, running the attachment bolts through the angle, and the angle running from the very top of the cowl to the toe kick. AND to the dashboard. This install ('38 Chevy, '51 Chevy) stopped VERY well.

    BTW, it works well to match the front calipers to the master/booster. Very well, indeed.


    P.S. Remember, these are your brakes, they need to be excellent.
  9. missysdad1
    Joined: Dec 9, 2008
    Posts: 2,992


    Your '56 may be different, but my '55 Special has a plenum on both sides of the engine as part of the firewall that would make installing a pedal/booster/master assembly awkward - unless you don't care how it looks.

    Carl's Automotive, the great shop in Red Oak, Texas, that did the chassis work on my car, installed a Corvette-style dual master in place of the stock master under the floor using the stock pedal assembly and push rod. I opted for non-power so the new master fit like a glove with only a few new holes needed to bolt it in.

    I have a disc/drum brake setup and the CPP Corvette-style master works great without a vacuum booster...but it does have a higher pedal effort than some might like. My car also has manual steering so non-power brakes is a good match.
  10. threewindow
    Joined: Nov 26, 2012
    Posts: 80


    bracing the pedal assembly to the dash keeps it from moving up and down under pressure on the back end of the assembly. with power brakes you hardly ever need to, put that much pressure on the brake pedal, so not so much of a problem. I braced mine because it was easy to do at the time I was building the car

Share This Page

Register now to get rid of these ads!


Copyright © 1995-2021 The Jalopy Journal: Steal our stuff, we'll kick your teeth in. Terms of Service. Privacy Policy.

Atomic Industry
Forum software by XenForo™ ©2010-2014 XenForo Ltd.