KJL

I have a 72 and am using a Holley 4150 carb w/typical throttle location. The total throttle travel is a function of geometry between the pedal and the mounting point on the carb throttle linkage. Have discovered that if i mount the cable at the typical mounting point on the carb and push the pedal all the way to the floor, the blades stop just short of 100% open. There does not appear to be an easy way of correcting this without somehow modifying the pedal or carb mounting point in some way.

Looking to see what other have done who may have had similar issues.

widowmaker221

Purchase an adjustable throttle bracket from Jegs etc fo this problem.

KJL

I have an adjustable bracket. With it set for max travel, (cable mounting is pulled back to furthest point before opening throttle blades) it is still coming up a bit short. What I need now is a tad more travel (1/4") in the cable. The only way I can see this happening is to change cable mounting point on the carb to increase the arc stroke or modify stroke at the pedal some way.

jim-81

You've probably checked this, but could the pedal be hitting the carpet?

KJL

Yes, I looked at that. It is frustrating because I just need a little more. I bet many folks have this problem but don't know it. I became aware of while on a chassis dyno. May not make a huge difference but still would like it to open 100%.

Richard454

Since you have maxed out the travel- why don't you change the position on the throttle lever- move the mounting down will increase the travel-might need to drill the lever.

edit*****you have the right idea****

See my crude pic below-




Took me some time -but got all 12 of mine to open all the way!!!

C3 Stroker

I had this same problem with my '69 some years back. This problem happens to other years also. You have to straighten the gas pedal assembly rod, which gets stretched from wear.

Reference this thread for help...
https://www.corvetteforum.com/forums...l-linkage.html

KJL

Maybe it is time to just replace the pedal and cable. Didn't seem like there was much to adjust with the pedal. If I recall in my 72 it is just a single bent bar bolted to the floor board

C3 Stroker

Yes, the '72 has a single bar vs. the 2-piece '69 style. This was to correct the problem, but the new style also gets bent from use (stretched). It can be bent back, or replaced with a new one. Also, I replaced my throttle cable with a Lokar unit which has greater adjustability than the stock one. It will guarantee you total throttle ability.

KJL

Do you recall what Lokar model? Was it a direct bolt in? I checked out their site but could not locate a specific model for 1972 vettes.

KJL

That would be the solution but the Holley throttle bracket has lots of holes in it and unfortunately makes it difficult to precisely locate a new location.

C3 Stroker

This one....the universal 24" model.....bolts in ....you can actually cut it to fit, but it's not necessary......
http://www.summitracing.com/parts/lo...000u/overview/

Also used this bracket; you can tighten this one against the Holley carb base snuggly...http://www.summitracing.com/parts/lo...4000/overview/

KJL

Was passing the cable through the fire wall an issue?

C3 Stroker

Not really an issue......it's been almost 10 yrs, but I do remember having to "contort" somewhat to reach a bolt, though. Also save the plastic retainer by the little "ball" on the stock cable where it attaches to the gas pedal...you'll need it for the new one.

KJL

OK Thanks, My seats are out so this is a good time to check this stuff out.

69Vett

1 bolt to remove cable assy. on the inside, easy to say,
Not so easy to get to ...
I would just bend the pedal rod back, to gain your cable travel back to normal.
(very common problem) it seems people like to mash Corvette gas pedals frequently !
good luck.

69427

Just a quick thanks to the OP (for his timing) and to the contributors in this thread. Last year at a track day I just got this SOTP feeling that the engine just wasn't pulling as hard as it should or used to. Been meaning to track down the reason, but been busy over the winter doing some suspension changes. After seeing this thread I went out and checked the throttle blades at pedal "WOT", and I've got an issue with the pedal assembly. As soon as I get the suspension back together I'll fix the pedal issue.

Thanks again!

CanadaGrant

I recently replaced the cable in my 69 BB and found that the original was stretched a quarter inch longer than the replacement. Also, the pedal arc can be improved by bending the pedal arm back up to where it's supposed to be.

KJL

Looking at it now, There are 3 bolts that hold the pedal bracket in place. It looks like the bolt way up under the dash also holds the plate that the cable passes through. There is also what appears to be a rivet on the top of the plate visible from the outside. I am a little concerned about bending the bar with it mounted, thought I would remove it but that looks like a major pain.

C3 Stroker

Save yourself some agony.....remove the bar assembly; you'll be thankful for the time saved trying to fight it. That way you can put it in a vise to easily bend it.