Brake Pedal Differences in Height

Discussion in 'The whoa and the sway.' started by knucklebusted, Sep 15, 2020 at 10:47 AM.

  1. knucklebusted

    knucklebusted Well-Known Member

    So, I have a factory 70 car with front disc brakes that I've upgraded 4 wheel discs. The brake pedal is close to the floor, about even with the throttle pedal and engages after a slight distance is moved.

    I also have a 71 4-speed car that was 4 wheel drum before I converted to front discs. The brake pedal is also close to the floor, about even with the throttle pedal and engages after a slight distance is moved. Also, the clutch pedal is much higher than the brake pedal. I see a lot of guys at cruise-ins with the brake and clutch level even with power brakes. Have they monkeyed with the pedal to get that?

    We just put a wrapped wheel on a buddy's 71 car with factory front discs. When I drove it into the garage, his brake pedal engages as soon as you touch the pedal.

    What is different about these cars that I've not noticed until now? Did someone put my buddy's brake rod in the wrong hole? I haven't investigated further yet as we were working on the steering wheel.

    Buddy's brake pedal.
    [​IMG]

    Four speed car pedal, also the clutch is much higher than the brake.
    [​IMG]

    70 car
    [​IMG]
     
  2. BrianTrick

    BrianTrick Brian Trick

    Power brake cars will have the pedals uneven and manual brake cars will have them even.
     
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  3. knucklebusted

    knucklebusted Well-Known Member

    All of these cars are power front disc with my 70 being a 4-wheel-disc in the rear. All the front discs are factory rotors, boosters, calipers and either original or replacement master cylinders.
     
  4. LARRY70GS

    LARRY70GS a.k.a. "THE WIZARD"

    When I replaced my booster with a reproduction unit, the rod was threaded with a nut that you could adjust the resting pedal height. Take a look under your dash.
     
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  5. TrunkMonkey

    TrunkMonkey Well-Known Member

    In addition to Larry's reply, some pedals have two holes, upper and lower for the ratio. Upper for manual and lower for powered brakes.
     
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  6. Bens99gtp

    Bens99gtp Well-Known Member

    size if master cylindeg and caliper puston size and how the reae brajes are adjusted will drastically effect how much pedal travel obe has b4 pedal firms up.

    A longer or shorter rod will effect pedal free height.......but too short could effect total travel if needing travel and rod is too short....

    After switching to my wilwoods on all 4 corners and matching master........i have as much adjustment out as I could......i feel I could use a little higher pedal and height.....but im out of room to adjust.....need to wrld a few nuts together and to my clevis to get more height
     
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  7. knucklebusted

    knucklebusted Well-Known Member

    But if you used the manual brake hole it is the higher one with a much lower mechanical advantage and the pedal travels farther. I know my 71 conversion and my 70 are definitely in the lower hole. I'm pretty sure my buddy's car is in the right hole too because the power booster angles up on the firewall and the rod angles down. I think you'd have to bend the booster rod to get it to work in the non-power hole on the pedal lever.
     
  8. BrianTrick

    BrianTrick Brian Trick

    I was being more specific to 4-speed cars,or ones that have a clutch pedal. The manual brake cars have the pedal even and the power brake have them uneven. The clevis for the manual brake goes in the upper hole on the pedal,power goes on the lower hole.
    You could still have some variances from this,depending on how things are installed or adjusted. The 455 z-bar vs the 350 z-bar can effect that too.
     
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  9. knucklebusted

    knucklebusted Well-Known Member

    I'm not really worried about the clutch pedal, it is where it is. It was just glaringly obvious that my two cars brakes are very similar while my buddy's car was much different.

    As I consider other possibilities, I've thought maybe his booster isn't as strong and the pedal met resistance sooner but it still stops fine. My other thought was his master cylinder moves fluid as soon as there is movement while mine both appear to have some distance before the brakes actuate but mine still stop with the pedal off the floorboard.

    I don't suspect anything is wrong with any of our cars but the difference was apparent. If I drive my wife's Honda HR-V after driving my Lexus GS, I will throw you through the windshield because it takes a much lighter touch on the 2900lbs Honda than the 2-ton AWD Lexus.
     

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