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Are you dead set on doing a Turbo? If you go for the entire 95 SSEi engine/Trans/PCM combo it would be easier to leave it Supercharged.. And Go to turbo later maybe? This way you can leave the stock tune and have good driveability..

When you want to turbo later you could gut the SC, use a block off for the nose drive and set it up for turbo..

phoenix_flame220 wrote:Say for example I found a 95 SSEi donor car and converted it to turbo the way you said, what kind of tuning changes would have to be made to the PCM? Since its already set up for boost would it be usable as is? Would the vacuum lines have to be moved to the inlet of the turbo now that the manifold is positive pressure? What about the MAF?

You really should look at some turbo kits and builds for the 3800, not a lot has been done here on, and there's not really anyone active who has first hand knowlege of a Turbo build.

I have been thinking toward the idea of having a 95 powertrain like you said, then converting it to turbo later if i choose to. I plan to do a remote turbo installation anyway so I wont have to pull the motor again. I have a question about PCMs though. What will happen if a turbo is used with the stock pcm? I know a tune will be needed, but does anyone know how it would react the way it is? Im looking at as many turbo builds as i can, but I havent found a definitive answer as of yet. Also, what happens if a PCM is used with a non electronic tranny but the tranny values are not deleted? Im not asking for the sake of using my tranny, just in general.

phoenix_flame220 wrote:I have a question about PCMs though. What will happen if a turbo is used with the stock pcm? I know a tune will be needed, but does anyone know how it would react the way it is? Im looking at as many turbo builds as i can, but I havent found a definitive answer as of yet. Also, what happens if a PCM is used with a non electronic tranny but the tranny values are not deleted? Im not asking for the sake of using my tranny, just in general.

If the PCM (if you use a 1997 and up) or the MEMCAL (94/95) isn't reprogrammed, your boost control will be awful. The computer will still think a supercharger is in play, which as you know delivers power much differently in both function and in powerband location than a turbo does. Boost control, timing, and injector pulse widths (and possibly injectors themselves) will have to be changed. Since all that has to be changed, might as well have all the trans values and associated codes nulled out at the same time. If not, you'll throw a CEL and possibly a limp home mode.

is it possible to tune the stock pcm to control everything without having to add a stand alone system?

That's basically what I just said in the post above yours. Factory control computers will work just fine...it's the numbers inside the bin file that need to be changed.