Easiest Way to Shoreten Cable Pull @ TB?
Thread Starter
TECH Resident
Joined: May 2004
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From: SoCal
Easiest Way to Shoreten Cable Pull @ TB? On my conversion I'm maxed out on the amount of cable pull I have available at the gas pedal linkage, so I'm looking to see if there's something I can do to modify the throttle body. Basically, I can't quite get full throttle and my gas pedal travel is currently a bit more than I'd like. Any suggestions on a simple mod?
Thanks,
Andy1
Thanks,
Andy1
)- they will have a cable stop. I would not mess withthe TB end - just shorten at at the pedal. Thread Starter
TECH Resident
Joined: May 2004
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From: SoCal
Hmmm, I can see that I didn't make it very clear what I'm trying to accomplish.
The lever ratio (actually reduce the radius of the pulley) on the throttle body is what I'd like to change. So, I want to decrese the amount of cable pull required in order to fully open the throttle body.
Suggestions?
Thanks,
Andy1
The lever ratio (actually reduce the radius of the pulley) on the throttle body is what I'd like to change. So, I want to decrese the amount of cable pull required in order to fully open the throttle body.
Suggestions?
Thanks,
Andy1
I had a similar problem on my swap that I fixed by removing the carpet under the pedal and adjusting the pedal stop.
Sometimes you can put an extention on the end of the pedal arm to increase the lever ratio. If that misaligns the cable with the opening in the firewall, then you may need to either drill a new hole or move the pivot point on the pedal assembly itself. Basically just increase the distance between the pivot point (fulcrum) and where the cable hooks to the pedal assembly.
Like you suggested a smaller diameter TB pulley would cure the problem.
If none of the above work, then you can install some sort of jackshaft under the hood to increase the lever ratio.
Sometimes you can put an extention on the end of the pedal arm to increase the lever ratio. If that misaligns the cable with the opening in the firewall, then you may need to either drill a new hole or move the pivot point on the pedal assembly itself. Basically just increase the distance between the pivot point (fulcrum) and where the cable hooks to the pedal assembly.
Like you suggested a smaller diameter TB pulley would cure the problem.
If none of the above work, then you can install some sort of jackshaft under the hood to increase the lever ratio.
On The Tree
Joined: Jul 2004
Posts: 148
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From: St. Louis
I agree, try and get the extra travel at the pedal, move the pivot or perhaps trim the back of the pedal for a little extra movement, i don't know how you could do it at the throttle body without a different cam shape or size. maybe different ls1 cars had different tb pulley? pictures might help of the pedal assembly
Thread Starter
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Joined: May 2004
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From: SoCal
My conversion is a Porsche 914. There's a pushrod from the pedal to a bellcrank. The throttle cable attaches to the bellcrank. I have already increased the lever ratio of the bellcrank to its maximum; any more misalignment, and the cable will grate against the throttle cable tube (a steel tube that runs down the center tunnel to the engine bay). Also, the bellcrank rotates only so much before it hits the floorboard. As you might imagine, there's very little room in a 914 aseverything is real tight.
I was looking for some ideas that perhaps I overlooked. I do have a machine shop where I can fabricate just about anything I need. Pop N Wood's jackshaft idea is interesting; thanks! I may opt to make a new pulley at a slightly smaller diameter and attach it to the side of the existing pulley, then make a cable bulkhead that's offset enough to line up with that new pulley. I'll think about it some more.
Thanks,
Andy1
I was looking for some ideas that perhaps I overlooked. I do have a machine shop where I can fabricate just about anything I need. Pop N Wood's jackshaft idea is interesting; thanks! I may opt to make a new pulley at a slightly smaller diameter and attach it to the side of the existing pulley, then make a cable bulkhead that's offset enough to line up with that new pulley. I'll think about it some more.
Thanks,
Andy1
