Just did a LT1 intake swap and the throttle cable bracket was moved forward 1 1/2 inches after the swap. I shimmed the TV cable before the black plastic connector thing to take up the slack. Got a line pressure gauge to see what's going on.

This is a pro-built tranny about 4 years old. Pressure at idle at min TV is 100 psi in park, 160 in R, 100 in N, OD, and D, and 210 in 2nd and 1st.

Pressure at high idle full TV is 200 in P, 300 in R, 200 in N, OD, and D, and 210 in 2nd and 1st.

The book gives normal idle min TV pressure as 75-100 psi. I can adjust the line pressure at idle all the way up to 150 psi.

My question is:

If 100 psi at idle is good, then is more harmful to the tranny?

If the 700R4 functions off of line pressure, shouldn't running max line pressure make the tranny stronger, shift harder and stand up to more power?

How much is too much?

 

:lala:

 

Not sure if this will help, perhaps Dana can chime in..

When I was researching where to buy my tranny(in the end I bought a Pro-built) I spoke with a guy names Steve over at 700r4.com. He was very helpful and I remember him mentioning that when you install on if his trannies that you should also buy one of his install kits(I think thats what he called it). Anyway, during this conversation he said the the kit included a pressure gauge and some hose that allowed you to test the line pressures. I dont recall all of the details but perhaps he might be able to give you some advice. Good luck.

 

Higher pressure makes for increased strain on the Pump, seals and generates the chance for crossleaks. Use what you need. I would set it up to have minimum (78) at idle but as soon as the car begins to move you should be seeing line rise.

 

Have you called ProBuilt about it, then? I'm sure they'd know best...?