My 86 IROC when the tv cable is not connected, has long drawn out shifts, and shifts hard. I thought when the tv is not connected, the gears will stack and shift too fast. I am thinking I have a valve body w/ constant pressure. Can this be confermed w/o taking the pan off and checking??

This is normal for a stock GM transmission without a valve body kit. It just kept you from "wasting" your transmssion. Put the TV cable back and adjust it correctly.

I did connect it back right away. I was told or I read that when it is not connected, it will shift fast, and early, and "stack" when it is not connected. Is there any thing to what I was told?

The TV

The TV is more than just shift timing, it is also line pressure. You must never drive without it, even half throttle without the pressure rise can kill a 700. I've done it.

Thankyou atilla. I know the tv cable controls pressure and it's bad to not have it hooked up. I unknowingly drove it over 80 miles w/ it not connected, and it didn't ruin the tranny. Usually that kind of luck doesn't come my way. Anyway I took it to a tranny rebuilder, and he gave it a clean bill of health. I was amazed it didn't blow and so was the mechanic. But fact is it went that far and didn't burn the tranny. By the way, I bought the car that way not knowing the tv cable was unhooked.

Pro Built is right, it will live with the cable completely unhooked. There is actually a big checkball that allows high line pressure to save itself. However if the cable is misadjusted/too loose it will shift soft and quickly and burn itself up.

that's interesting. I thought if the cable was unhooked, it would stack.. shift way too soon, but I learned something. I about had a kitten when I found out it was unhooked. It is shifting fine now, the fluid remained pink and unburnt, and I was relieved when I found out it is still ok. What if the line pressure is too high? Or is there such a thing as too high?

If the pressure is high you will have hard shifts. High pressure just makes the pump work harder.

is making the pump work harder bad?

High line pressure is always hard on pumps, especially at lower rpm's.

Hey Pro Built, I was reading about constant pressure valve bodies that keep 200 psi regardless of the tv cable hook up. Would this be hard on the pump? is 200 psi at low revs too much on the pump??

I do not use them, or recommend them. When the TV cable is set right, and the right things done to the valve body/pump, there is no better way.

I know this thread is old, but would a constant pressure valve body be hard on the tranny pump? If not why do you not recommend them?

The pump is not designed to handle high pressure at low rpm's and all of the time. They wear at a very high rate when at high line pressure all of the time. It is also very hard on the sealing rings, splines, and everything else in the gear train. That is one reason I do not recommend them. Dana

I would concur with Dana on the constant presure valve body. I think they are a bad idea.

I'm sure your reasons are good, but what is wrong with constant pressure valve body?
I am editing this post. I forgot to read probuilt's statement. I'll pass on the constant pressure valve body. Thanks for the advise..

I have an additional question on the TV cable hook up. I purchased an 84 Z28 which was in a pile of parts in a guys garage. I had the 700R4 transmission rebuilt as well as the 305 engine. The car came with an Edelbrock 1406 carb. I cannot figure out where the TV cable hooks up to the carb, or the cruise for that matter. A picture would be great. Looking at the Edelbrock website (vidoes) linked somewhere on here also talked about a vacuum line from the carb to the transmission. The line the Edelbrock spokeman talked about was plugged when I got the car. Sorry this is so long but could use some help as I get ready to start this girl up.

It sounds like your carb was not set up for tv linkage. I had a similar issue with my carb. It had no linkage to hook the tv cable to, so I made my own. I had to make sure the geometry was just right. It works well now. I wish I had the dot com sight, but I don't. Just google 700r4 tv linkage, and you will find an abundant amount of info.

Stev, thanks I found a couple links by searching TV cable on this site. Any help on the cruise set up or vacuum line?

If you mean vacuum line to the tranny, I don't believe there is one. I don't know about cruise. I never had to deal with it. My cruise on the IROC flew south anyway. I am still used to cars with out cruise. Back in the 60's and early 70's, only personal luxury cars had it..

The first car I ever special ordered was a 1984 Berlinetta. It was loaded, including cruise. I do a lot of driving so cruise is nice.