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Gas pedal pressure & Shifting 1st to 2nd gear

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Old 06-22-2020, 02:17 PM
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Gas pedal pressure & Shifting 1st to 2nd gear

Hoping someone can give me some help with the following.

I have a 1984 Z28 that I converted to a Holley Sniper EFI. I’ve been driving it for a while and the engine runs fine but the gas pedal is very hard to push initially when you put it in drive and when it shifts from 1st to 2nd gear it shifts hard and squeals the tires a little a it shifts. It shifts just fine through the rest of the gears.

Any suggestions to try would be greatly appreciated.

Thanks.
Old 06-22-2020, 02:20 PM
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Car: 86 Imponte Ruiner 450GT, 91 Formula
Engine: 350 Vortec, FIRST TPI, 325 RWHP
Transmission: 700R4 3000 stall.
Axle/Gears: 9 Bolt Torsen 3.70
Re: Gas pedal pressure & Shifting 1st to 2nd gear

Return spring is probably too strong, and the TV cable isn't adjusted properly. Too tight resulting in high line pressure and shift delay's.

GD
Old 06-22-2020, 02:35 PM
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Re: Gas pedal pressure & Shifting 1st to 2nd gear

Thanks for the quick reply. I was going to try and replace the spring, I have another donor Z28 I used for this car that I can swap the spring out with.

I’m kind of learning as I go with some of the things on the car, so when you say TV cable is that the cable that runs from the gas pedal to the throttle bracket? if so when you say adjust what exactly do you mean. I know when I look at how that cable is connected to the bracket is goes around the bolt through a kind of elliptical hole and looks like the bracket is sort of pushing or twisting the cable to the right of the bracket through the hole. So,I’m not sure how to adjust that.
Old 06-22-2020, 08:54 PM
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Car: 86 Imponte Ruiner 450GT, 91 Formula
Engine: 350 Vortec, FIRST TPI, 325 RWHP
Transmission: 700R4 3000 stall.
Axle/Gears: 9 Bolt Torsen 3.70
Re: Gas pedal pressure & Shifting 1st to 2nd gear

No the TV cable is the Throttle Valve cable for the transmission.

It needs to be adjusted so that it is as tight as possible at WOT. The TV cable is self-adjusting - you push the button on the side and slide the inner ratcheting mechanism all the way toward the firewall then manually twist the throttle to the WOT position and the cable should ratchet out to it's correct position.

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Old 06-22-2020, 09:13 PM
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Re: Gas pedal pressure & Shifting 1st to 2nd gear

Ok. Thanks for the help, I’ll give that a try tomorrow.

I’m assuming that if I can’t do it myself I can take it to a transmission shop and they could adjust it.

Thanks again.
Old 06-23-2020, 07:12 AM
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Re: Gas pedal pressure & Shifting 1st to 2nd gear

The potential problem with taking that to a shop is that many technicians who have not been rebuilding transmissions for more than 25 years will not have much of a clue about the nuances of adjusting a TH700-R4 cable. They will be just as confused as you, probably not having touched one to 20+ years.
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