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Throttle linkage for FITech

Old 05-23-2016, 05:18 PM
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LT2300
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Default Throttle linkage for FITech

I've looked through the threads and haven't seen this particular issue addressed. I just installed an FITech Go EFI. The unit is still learning, but has quickly come up to speed. Everything about it is positive, with one exception, totally unrelated to the FITech system itself.

My car is a '69, original 4-speed with the cable throttle linkage. No matter what I do, I can't get the cable to accommodate full travel at the throttle body. With the pedal to the floor, it's about 3/16" of cable travel short to get to WOT. If I try to fudge the cable lockdown location to enable it to get to WOT, then there isn't enough slack to allow it to return to idle.

I took it to the local speed shop, and they didn't have a solution. At best, they're talking about having to replace everything from the gas pedal to the end of the cable.

Anyone face / solve this problem? Thanks.

Last edited by LT2300; 05-23-2016 at 05:19 PM.
Old 05-23-2016, 05:54 PM
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Richard454
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A bellcrank.... Post up a picture Mines a little extreme- but a few parts from speedway motors and I was there.
Old 05-23-2016, 05:58 PM
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ddawson
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Cable may be stretched. What I did.

Clip on fishing weight. Drill a small hole and clamp it on. See if the takes up the slack.

I'm waiting for my new cable to arrive.
Old 05-23-2016, 07:29 PM
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Originally Posted by Richard454
A bellcrank.... Post up a picture Mines a little extreme- but a few parts from speedway motors and I was there.
Your picture didn't come through... In the interim, I'm going to look at what Speedway has, to see if I can find something.

Last edited by LT2300; 05-23-2016 at 07:39 PM. Reason: add detail
Old 05-23-2016, 07:37 PM
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Originally Posted by ddawson
Cable may be stretched. What I did.

Clip on fishing weight. Drill a small hole and clamp it on. See if the takes up the slack.

I'm waiting for my new cable to arrive.
Cable's not that old, and the issue isn't cable length. The cable can only move (these are hypothetical numbers / approximations) three inches and I need 3 3/16" travel to get the butterflies to WOT. The 3/16" fraction is not an approximation -- that's how much short of WTO I am. Per the previous answer (Richard454), some sort of bell crank that trades slightly increased effort (due to reduced mechanical advantage) for a little more movement might do the trick. I'm hoping to get a look at his setup. Thanks.
Old 05-24-2016, 12:22 AM
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That's a video....

Here's some pics-like I said -mines just a little over the top-

Used the stock pedal and linkage- made a bracket for the double bellcrank-





DSCN5168 by Richard Hayes, on Flickr
Old 05-24-2016, 12:31 AM
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I recently discover I have the same issue on my 69 with a 350/350. I have not had time to dig into the solution. Please keep me (us) posted on how you resolve the issue. I thought I was just going to modify the bracket position that holds the cable? Maybe you will find a better solution. Thank you.

My car is a '69, original 4-speed with the cable throttle linkage. No matter what I do, I can't get the cable to accommodate full travel at the throttle body. With the pedal to the floor, it's about 3/16" of cable travel short to get to WOT. If I try to fudge the cable lockdown location to enable it to get to WOT, then there isn't enough slack to allow it to return to idle.

I took it to the local speed shop, and they didn't have a solution. At best, they're talking about having to replace everything from the gas pedal to the end of the cable.

Anyone face / solve this problem? Thanks.[/QUOTE]
Old 05-24-2016, 09:04 AM
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OK..I looked at the FITech- just standard carb linkage.



Can you not move the throttle cable to the lower hole...If you are already using the lower hole you could drill another one lower. That shouldl get you the more throttle movement you need...

Post up a picture-


Old 05-24-2016, 10:54 AM
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tshort
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If you can't solve it by using one of the lower holes on the linkage then your actual pedal is probably bent. Many of us have found this to be a problem (I did on mine) even when using a carb. Solution is to take out the pedal arm, put more bend back into it, and reinstall. If you do a search on this you should find a few hits. I think Jim (427HotRod) had a post about it a few years ago.
Old 05-24-2016, 11:33 AM
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1Fordman
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Had the same problem on the 68 L-71 tri-power. The 68-69 stamped steel linkages tend to bend. Got a 73 underdash linkage which is made of beefier roundstock that doesn't bend and flex, problem solved.
Old 05-24-2016, 12:46 PM
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It's a bent pedal or you're using the wrong hole on the linkage. A bellcrank is way overkill to fix this problem.

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