Bruce Amighty

I have an 87 700-r4. Just did a rebuild and had the tranny dynoed by a reliable shop locally. I put a 2000-2200 stall lockup converter on it. The shop tested the tranny with the stall converter and said I needed to use the original non lockup converter. They tested it with the non lockup converter and it tested fine. There is no wiring harness inside the tranny. There is no check ball in the end of the input shaft. In the pump, there is a just a lube valve in the lockup valve slot. The local tranny shop told me that if I wanted to use the lockup converter that I needed to put in a check ball in the end of the input shaft and install the lockup valve with the spring into the pump body. They said this would give me a hydraulic lockup without the computer or solenoid. I also have been told by another shop that the tranny should have come with lockup and it must have been converted to non lockup. they also told me the same as the other local shop that all I had to do was install the ball and the valve. Are they just blowing smoke up my skirt or is this all I have to do to use my high stall lockup converter?

Buisson91B4C93Z

Your car should already have lock-up setup. I know you have to have the valve and spring in place. I believe you have to have the tcc solinoid wired as well. The check ball in the input shaft on the other hand i don't use. I've never had a problem with that ball but i've had people tell me that it cause a lot of heat by restricting fluid. A few of the shops that build bullitproof 700rs and 4l60s remove the check ball and still use lockup converters. If these guys remove it and warranty it to 600 hp, i'd try it. I have removed that ball in the last 4 i've built for abuse and have had a lot of luck.

Bruce Amighty

So, I guess what I can do is reconnect the wiring harness to the transmission case, install the lockup valve with the spring and install the lockup converter and all should be fine. Any last words of encouragement before I do this?

Pro Built Automatics

What was brand, size & stall of the non lockup torque converter?

Bruce Amighty

I don't know the brand but it was a stock stall non lockup converter. The lockup converter that I have is one I purchased off ebay and is a 2000 2200 stall.

loneroad

iTrader: (3)

I have a hyd lockup, no computer and im looking to go up to a 3000 stall. Can i run a lockup or do i have to run a non lock up?