Carb help please

[Dibdob62]

Bit of a newbie question but what does this cable do and how do you set it up ?

It goes from the carb to the auto box (th350)

[71GMC4me]

That's the passing gear linkage I'm not to sure about the hook up though

[Secret Squirrel]

Drive the truck normal, after it shifts into second mash the pedal. It should downshift when floored while in second or third and shift normal while easy driving.

If you mash the pedal and the trans downshift you got it right. Adjust, test drive and repeat. Check the net, for a video.

[davepl]

I'm not sure I like the look of that linkage. Hard to say, but if that's not the factory setup which is intended to never bind, find the right part. If that washer-nut combo decides to bind and stick when you've got the throttle wide open it's going to ruin your whole day.

Either way, there's really no adjustment, unlike the TV cables on later transmissions. I think most of the shift action is really controlled by the vacuum modulator and valvebody programming. I don't remember being able to modify shift points or quality with the old TH350 or powerglide kickdown.

Essentially (and I am NOT a trans guru) I think it's a binary switch - if it's zero vacuum at the modulator, only downshift with sufficient throttle?

[geezer#99]

Originally Posted by davepl

I'm not sure I like the look of that linkage. Hard to say, but if that's not the factory setup which is intended to never bind, find the right part. If that washer-nut combo decides to bind and stick when you've got the throttle wide open it's going to ruin your whole day.

Either way, there's really no adjustment, unlike the TV cables on later transmissions. I think most of the shift action is really controlled by the vacuum modulator and valvebody programming. I don't remember being able to modify shift points or quality with the old TH350 or powerglide kickdown.

Essentially (and I am NOT a trans guru) I think it's a binary switch - if it's zero vacuum at the modulator, only downshift with sufficient throttle?

Really!! No adjustment!!
You should look here.
http://67-72chevytrucks.com/vboard/s...turbo+350+kick

[mechanicalman]

First off, I'm not sure you have the right detent cable for the application. That being said, the slot on the end of the cable I believe is supposed to slide freely, then when the throttle reaches a certain angle it reaches the end of the slot and pulls on the detent cable to activate a downshift. The cable housing pictures referenced by geezer show how to adjust that housing, it may take a few tries to get it right if it will work. Otherwise you may need to get a different detent cable.

[71GMC4me]

Try this link it has transmission pan layouts with names for gm transmissions
http://www.chevellestuff.com/images/auto_trans_id.jpg

[Dibdob62]

To start with I was having to rev the nuts of my truck to get it to change gear but I found the vacuum pipe was not hooked up, I have hooked it up to the carb on my other truck it goes to the manifold but on this one the brake booster is connected to this point and now it changes up to second just fine.

My problem at the moment is there doesn't seem to be a third gear its like lm driving round in second all the time ?

[71GMC4me]

I had a trans am once it did the same thing it turned out to be the modulator valve (the vacuum line hooks to it on the trans and fyi on the 350 turbo inside of the vacuum port is a slotted screw adjuster for shifting adjustment ) correct me if im wrong its been 20 yrs lol