Guys, My transmission that came with my car is a Turbo 400. To the best of my knowledge I was told that the valve body was modified to be a manual shift automatic and it does have a shift kit installed. Is it necessary to have vacuum to the transmission at all? My thinking was since it was manual shift automatic its not necessary.What the purpose if needed?
With a full manual conversion, I believe they eliminate the modulator valve and modulator, and there is a plug there. If you have a modulator you need it. The transmission uses it to gauge engine load and adjust line pressure among other things. It won't shift with no vacuum
