HI,
I have a 1990 iroc-z with the 350 ci and a 4L60. awhile back i had tranny work done and told the guy i was going to use a non loc-up converter. after i drove it a few times, was not happy with the loss of overdrive, so i installed stock converter...put it in drive and car stalled like i dumped the clutch in a standard..installed brand new street fighter converter...same thing..PLEASE HELP!!

 

You did not lose overdrive, just lockup. You will need to talk to the builder and see what modifications he did when going to a non lockup torque converter. He most likely will have to put back as a lockup unit now to work correctly with the new lockup torque converter. What type of torque converter did you use for the non lockup? What is the diameter and stall of this non lockup?

 

I purchased the non lock up from a company call oregon performance transmissions, not sure of diameter of non lock up, sold when i didnt want it anymore, the stall was 2500, and i have a 2500 stall on new lock up i have in now. Unfortunately the gentleman i had do the work is out of business now, i have tried to reach him multiplte times to no avail. Would i be better off replacing the pump and valve body, or maybe just get a reman tranny?

 

If you are using a non-lockup torque converter here, then most likely the TCC valve in the pump has been changed to a non-lockup valve. A TransGo is the most common. It can easily be undone, just replace it with a factory TCC valve from any 1993 and earlier 700R4 pimp. Any shop should have these and you will need an input shaft capsule and O-ring. If the wiring, with lockup solenoid and switch are missing, then you will need them from a 1987 and up unit. The 3-4 switch on the valve if missing will need to get one that is a normally open switch here. Any shop should have these and you will need an input shaft capsule (get a 1995 and up capsule) and O-ring for the input shaft. You should not be out over $25.00 & $35.00 at the most for this. If you cannot do this, a competent shop can do this easily.