Question on Holley carb throttle stud location

[dan juhasz]

Has anyone else run into the problem of the 66/67 b body gas pedal assembly not providing enough travel to attain full throttle on a 4150 Holley carb.
I’m currently using the 1/4 inch hole that is closest to the throttle shaft center line. A Lokar cable assembly but stock gas pedal and bell crank.
I get close probably 85/90 percent but not full throttle.

 

[pnora]

I have. I replaced the cable with one that has more travel. I used this one for my 69 from Mancini racing. MRE8668

 

[Black_Sheep]

Holley Throttle Lever Extension 20-7 is what you seek...​

 

[pnora]

Holley Throttle Lever Extension 20-7 is what you seek...​

View attachment 1419843

That might correct some of the geometry. If the poster is going through what I went through the cable will fix his issues. I was baffled and another member clued me in on the cable as he also had the issue.

 

[4mulas]

I don’t have the holley bracket that’s available as I have no need for kick down stuff (manual valve body).

finger points to the hole I used. Drilled out to 1/4 to accommodate the stud.

the longer cable isn’t the end all be all as you end up running out of pedal travel at the floor before full throttle.

 

[dan juhasz]

I don’t have the holley bracket that’s available as I have no need for kick down stuff (manual valve body).

finger points to the hole I used. Drilled out to 1/4 to accommodate the stud.

the longer cable isn’t the end all be all as you end up running out of pedal travel at the floor before full throttle.

View attachment 1420045

View attachment 1420046

View attachment 1420047

What you said is spot on. I have the Lokar cable, I’m not running out of cable I’ve run out of pedal travel. No way to change the pedal travel other than messing with the stud location on the carb to alter the ratio. I was hoping that a another solution would be available

 

[4mulas]

What you said is spot on. I have the Lokar cable, I’m not running out of cable I’ve run out of pedal travel. No way to change the pedal travel other than messing with the stud location on the carb to alter the ratio. I was hoping that a another solution would be available

Just drill the hole. You are only enlarging it a tiny bit. Yah I know, you’ll be thinking why am I drilling 800 dollar carb. Lol. But once you’re done and have full throttle you’ll get over it. Lol

Also, make sure you getting the most travel possible out of your pedal. The lever which holds the cable on my pedal was lazy and laid over from the factory. the maximum Distance from the lever where the cable seats in the lever to the base of the cable washer/clip (total travel) was about .750”. Once I aligned, straightened, and tweaked the lever I increased the lever travel to about 1.1” Which is a substantial gain. A small gain at the petal is even more at the throttle shaft.

I had 5 or 6 spare pedal/pedal brackets and the all ranged from .75” to about .950” at the most. Quite a varianc.

you‘ll probably find threads on people shimming and moving th whole bracket away from the floor and 1/8 - 1/4" but I don’t like that idea too much.

I didn’t take a picture of the lever after but it is aligned square and high. These show the poor alignment and lazy/bend

further to the first post - I have also read on several occasions and posts that the Holley bracket still leaves a lot to be desired in many cases. Ie: still didn’t get full throttle….

 

[dan juhasz]

Just drill the hole. You are only enlarging it a tiny bit. Yah I know, you’ll be thinking why am I drilling 800 dollar carb. Lol. But once you’re done and have full throttle you’ll get over it. Lol

Also, make sure you getting the most travel possible out of your pedal. The lever which holds the cable on my pedal was lazy and laid over from the factory. the maximum Distance from the lever where the cable seats in the lever to the base of the cable washer/clip (total travel) was about .750”. Once I aligned, straightened, and tweaked the lever I increased the lever travel to about 1.1” Which is a substantial gain. A small gain at the petal is even more at the throttle shaft.

I had 5 or 6 spare pedal/pedal brackets and the all ranged from .75” to about .950” at the most. Quite a varianc.

you‘ll probably find threads on people shimming and moving th whole bracket away from the floor and 1/8 - 1/4" but I don’t like that idea too much.

I didn’t take a picture of the lever after but it is aligned square and high. These show the poor alignment and lazy/bend

further to the first post - I have also read on several occasions and posts that the Holley bracket still leaves a lot to be desired in many cases. Ie: still didn’t get full throttle….

View attachment 1420582

View attachment 1420583

So less than 3/4 of an inch is shooting for when the pedal is as high as it can be. Is that correct?

 

[4mulas]

So less than 3/4 of an inch is shooting for when the pedal is as high as it can be. Is that correct?

yes. When the pedal was as high as it could go I HAD slightly less than a 3/4” gap between the lever and the cable seat/base. I wouldn’t shoot for that amount. I straightened it all got 1.1-ish gap, hence increasing the amount the amount of cable pull prior to the pedal bottoming out.

make sense?

you want more cable pull before the pedal bottoms out. The use the hole I suggested on the carb for the throttle stud and should be off to the races..

 

[oldkimmer]

Like said above I have had to tweet almost every car I’ve had. Kim