55.2-59 Brake vs Gas Pedal floor heights

[SideStepper]

I just installed a new CPP frame mounted power brake master cylinder under the cab with the original factory brake pedal as instructed. I also installed a new Lokar floor mounted cable type gas pedal assembly. I noticed that the brake pedal height off the cab floor sits much higher than the gas pedal. This must be a common problem within our hobby, but I have never heard any discusses about it. I find that the foot movement from the gas pedal to the high location of the brake pedal is extreme & uncomfortable. Can anyone provide their experiences on this pedal combination & possible fix?

[nvrdone]

Ive got an under floor mount brake system and I thought the brake pedal was too high. I shortened the brake pedal to match the clutch and its much better. Ive got a stock gas pedal so I cant comment on the gas pedal.

[51chevytruck]

I had the same issue on my 51 with their firewall mounted power brake booster kit. I called them and they sent me (sold me) linkage that enabled me to to adjust the pedal lower. I would call them, I'll bet they have run into this before.

Tom

[e015475]

I run a remote hydroboost under the floorboards with a Corvette master and I shortened the pedal length to the extent I could still get full stroke on the master with the pedal to the floor. The pedal rides about 4-5" off the floorboard and with the hydroboost working there's virtually no movement of the pedal during braking.

For the gas pedal, I'd make sure that when the pedal is all the way to the floor when the throttle blade is wide open - no sense in having the throttle pedal stick up any more than it has to

[nvrdone]

e015475: can you post pictures of your hydroboost set up. Im thinking of that as an upgrade. thanks

[dsraven]

hydroboost is great for these old trucks when you want a frame mounted booster. they give awesome boost and take less room. lots of guys use an astro van unit or something from a mustang. if scrounging at a wrecker take everything so you have what you need. lots of builders fab their own frame mount as well.
there is a guy in this thread that makes adapters but I think they are firewall mounts. some pics of the unit though for reference
http://67-72chevytrucks.com/vboard/s...d.php?t=347480
this fella made his own bracket for the frame mount. look around posts in the 70's for pics
https://67-72chevytrucks.com/vboard/...=283107&page=3

[MiraclePieCo]

The brake pedal sits higher off the floor than the gas pedal in virtually all vehicles. It should; it has greater travel.

[SideStepper]

Thanks for all the responses. My concern is that using the CPP frame mounted brake assembly, along with the original stock brake pedal (as instructed), locates the pedal height 9" off the floor. Most gas pedals are usually only 3", maybe 4" above the floor. I agree that the brake pedal is normally higher than the gas pedal, but not by 5" or 6".

Typically, when driving you mostly only need to pivot your heel to achieve normal acceleration & braking, rather than lifting your knee to your chin to reach the brake pedal. The suggestion to shorten the stock original pedal seems the best solution, with much care being given to maintain the correct stoke of the entire brake assembly. I don't understand how CPP could have missed this important functional requirement in their design & not even provide (or even mention) any possible solutions.

[jwhotrod]

the other thing you need to watch is where the gas pedal is at full throttle. The pedal needs to rest on the floor/stop at full throttle before you reach the carburetor linkage hard stop. if you dont you will pull the cable end off your throttle cable leaving you without throttle response. the little ball on the end of the Lokar cable will pull off. they will be happy to sell you a replacement, but that doesnt do you any good if you are out on the road.

[SideStepper]

jwhotrod......Thanks for your confirmation, I agree with you 100%.
I put in a lot of well spent time & effort to set the accelerator cable correctly to make sure of proper WOT & stop settings on both the gas pedal assembly & carb. As you know, the accessibility under the cab at the firewall is challenging, plus the fact that you're jumping back & forth, up & down to check the carb linkage set-up under the hood. It sure makes for a full day's worth of work, but I wouldn't have it any other way.

[mrbuck]

I’ll be running into the same problem, I’ve mounted the booster under floor, mine came with new pedal . But still sits 8 inches off the floor/firewall. I plan to shorten the linkage between the booster and brake pedal. Is it stands the linkage is about 7 inches long I plan to shorten to around 4.

[e015475]

nvrdone-

You can see photos of my Hydroboost setup in my build thread here-

https://67-72chevytrucks.com/vboard/...d.php?t=725080

Look at posts 80. 136 and 169

As dsraven suggested, this is a unit off of an Astrovan in the junkyard - think I paid $15 for it.

Brackets for the booster are available and make fabing a bracket much easier. You can see some here-

http://67-72chevytrucks.com/vboard/s...d.php?t=347480

I had to run mine upside down - seems to work just fine

[MiraclePieCo]

I guess I should have told you that to get my brake pedal at that height in the photo I had to cut and re-shape it until it was in a comfortable position.