Gas pedal throw issue

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1969dodgedart

Big Block 440
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I've got a problem with not enough gas pedal / cable travel . When the cable is attached to pin on the carb at idle position with no play and then you press the pedal down to the floor its not fully opening the carb butterflies . Seems like it needs another 1/2" of travel on the cable/ pedal . Any suggestions?
 
You'd have to show us a pic of the carb throttle arm, but certainly sounds like it's longer than stock from butterfly shaft to cable pivot.
 
A pic of your setup would be nice, as would info on what carb setup you have. However, I'll take a wild stab at this and say that you're trying to run your Mopar cable to the Chebby/Ferd linkage points on your carb. Holley and Edelbrock both sell Mopar carb linkage adapters for their carbs that must be used to get your pivot points correct. This also affects your kickdown linkage.
Edelbrock Throttle & Auto Trans Kickdown Bracket #8021 Chrysler & Holley® Double Pumper 8021: Advance Auto Parts
 
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You'd have to show us a pic of the carb throttle arm, but certainly sounds like it's longer than stock from butterfly shaft to cable pivot.
20201224_133950.jpg
 
I had this issue when I went to Holley Sniper. My pedal arm is held on the shaft by a spot weld. I ground it off enough to be able to twist the arm on the shaft and add more pedal throw, took about a half dozen test fits to get it right and rewelded it. Pedal felt a bit strange initially as it sits up a little higher but got used to it quickly
 
Following for same type of problem. When I take out all the slack my pedal/throttle sticks slightly open though.
 
I've changed return spring pivot mount and throttle cable pin location back / forth a few times before posting . When I changed mount locations I got the travel I was looking for but fairly stiff pedal . Wasn't sure if factory cable could take the strain . Just looking for Intel. Thx
 
I've changed return spring pivot mount and throttle cable pin location back / forth a few times before posting . When I changed mount locations I got the travel I was looking for but fairly stiff pedal . Wasn't sure if factory cable could take the strain . Just looking for Intel. Thx
Get your linkage pull correct, then you can play with return spring tension and/or mounting points to get an acceptable pedal feel.
 
Factory cable is hearty, most after market cables would have separated by now.
 
Hard to tell from the picture. The stud looks a lot closer to the primary shaft C/L on this 3310. Kind'a looks like you are pulling upward as well. ..............
upload_2020-12-24_14-10-14.png
 
Maybe this might help you...I've been down this path and it took me a lot of time/effort/aggravation to get it right. I had the same issue where I couldn't quite get the throw correct and if I did, the throttle would stick a little bit open. You may be working on a big-block so I'm not sure how this translates but I see from your pic that you are using the same throttle spring/cable bracket from Summit that I am. So I'll share what I did and maybe it will help.

For my 408 in my 72 Demon, with an 850 DP Holley and a Super Victor intake manifold, the carb sits up pretty tall. So a couple spare cables I had would not work. Nor would the original stock cable from my 71 Demon 340. Arrgghhhh...what a stupid problem to have to work on..... But of course without a properly functioning throttle cable, you don't have much to crow about!

So I took a bunch of measurements of what I had and talked to a guy at Pioneer auto parts (their cables are sold through Summit) and he was kind enough to get me a few measurements from some of their cables. So I ordered 4 of them from Summit in hopes I could make one of them work. Here is a little picture/table of the measurements of the cables (DCM is just my initials in the table). As noted, I ended up using #8420 and it allows for full throttle travel without any throttle hang-up at idle. The one I used has the "square" end where the plastic end pushes through the pedal and the legs "pop open" to hold it there. I prefer the "round" style with the clip that holds them in but I didn't end up with any that would work. Since the #8420 does not have the flare to hold it in the bracket, I had to use the set screw that is on the back side to hold it there.

Hope this helps - good luck!!
upload_2020-12-24_15-50-1.png


Now if I can just address the fact that the return spring holder arm hits the bottom of the 5" air filter base.....
 
When your carb is full closed, (ie not on fast idle cam) and the pedel cable is pulled all the way out. Take a pencle and mark an arch on the lever under the pivot post.

With the carb full open and the gas pedel held on the floor (brick?) And the cable held taught. Make the same mark on the lever under the pivot post.

Where the two arcs intersect should get you full open and full closed.
 
Maybe this might help you...I've been down this path and it took me a lot of time/effort/aggravation to get it right. I had the same issue where I couldn't quite get the throw correct and if I did, the throttle would stick a little bit open. You may be working on a big-block so I'm not sure how this translates but I see from your pic that you are using the same throttle spring/cable bracket from Summit that I am. So I'll share what I did and maybe it will help.

For my 408 in my 72 Demon, with an 850 DP Holley and a Super Victor intake manifold, the carb sits up pretty tall. So a couple spare cables I had would not work. Nor would the original stock cable from my 71 Demon 340. Arrgghhhh...what a stupid problem to have to work on..... But of course without a properly functioning throttle cable, you don't have much to crow about!

So I took a bunch of measurements of what I had and talked to a guy at Pioneer auto parts (their cables are sold through Summit) and he was kind enough to get me a few measurements from some of their cables. So I ordered 4 of them from Summit in hopes I could make one of them work. Here is a little picture/table of the measurements of the cables (DCM is just my initials in the table). As noted, I ended up using #8420 and it allows for full throttle travel without any throttle hang-up at idle. The one I used has the "square" end where the plastic end pushes through the pedal and the legs "pop open" to hold it there. I prefer the "round" style with the clip that holds them in but I didn't end up with any that would work. Since the #8420 does not have the flare to hold it in the bracket, I had to use the set screw that is on the back side to hold it there.

Hope this helps - good luck!!
View attachment 1715656648

Now if I can just address the fact that the return spring holder arm hits the bottom of the 5" air filter base.....
20201224_161209.jpg
 
The farther away from the throttle shaft of the carb you attach the throttle cable, the less the carb will open with any given amount of cable travel. You have to picture what's going on: you have a throttle lever on the carb, pivoting about the carb throttle shaft at the bottom. As you pull on the throttle lever with the cable, the cable attaching point moves in an arc, not a straight line, no matter where you attach it. Attach the cable close to the pivot, the arc is short, and a very small distance of cable travel will move the throttle many degrees. The farther away you attach the cable, the larger the arc, and the fewer degrees the throttle shaft will turn with a given amount of cable travel. That's why WHERE you attach the throttle cable on the throttle lever is so VERY important to get full throttle opening. Don't know how many jerry rigged setups I've seen where you know that the carb can't fully open. Easiest way to ensure proper throttle opening is to use the Holley or Edelbrock Mopar carb adapter referenced above.
 
You need the 20-7 Holley Chrysler adapter. When people don't use these Edelbrock 1481 and Holley 20-7 adapters they will always have a hard time getting it RIGHT!
 
You need the 20-7 Holley Chrysler adapter. When people don't use these Edelbrock 1481 and Holley 20-7 adapters they will always have a hard time getting it RIGHT!

And yet they fight you every step of the way. Crazy man. Crazy.
 
I've got a problem with not enough gas pedal / cable travel . When the cable is attached to pin on the carb at idle position with no play and then you press the pedal down to the floor its not fully opening the carb butterflies . Seems like it needs another 1/2" of travel on the cable/ pedal . Any suggestions?
I admit I only read ur post. What happens from over the years is that the pedal assambley gets bent down. Pull up on the pedal some then check it. U may need to do this a few times. Kim
 
And yet they fight you every step of the way. Crazy man. Crazy.
Some people don't bat an eye at dropping 400, 600, 800 bucks or more for the latest, purtiest, trickest carb on the planet but scoff at a $20 part to make it actually fit and work right on a Mopar. :BangHead:
 
Some people don't bat an eye at dropping 400, 600, 800 bucks or more for the latest, purtiest, trickest carb on the planet but scoff at a $20 part to make it actually fit and work right on a Mopar. :BangHead:

I used the Mopar adapter & it still didn’t fix my problem. Still had to bend the pedal up like Kim suggested
 
you have two or three separate and distinct problems, maybe four;
1) incorrect pull ratio
2) stiff operation,
3) possible limited travel of the cable caused by that overly long cable-protector;
4) possible limited travel of the pedal.
Fix them from the top down.
 
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you have two or three separate and distinct problems, maybe four;
1) incorrect pull ratio
2) stiff operation,
3) possible limited travel of the cable caused by that overly long cable-protector;
4) possible limited travel of the pedal.
Fix them from the top down.

Yes: Start with hooking the cable to the carb at the correct spot. Once you have that right, go from there.
 
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