Inherited 1997 v6 for use as beater track day car. Thinking of swapping 1997 v6 to new edge type v6. Can get motor pretty cheap at junkyard,does it use the same CPU and harness?
I'm assuming that you are looking to swap the V6 from a 1999+ into your 1997.
Short answer. No.
The 1996-1998 is a very different car electrically than the 1999-2004 model year. Trying to transplant a different model year PCM any other model year isn't likely to end well. The best chance of success is to retain as much of the originals car's wiring and electronics.
If looking for a pure "plug and play" swap, this is not it. The newer V6 will have things like:
A cylinder head temperature (CHT) sensor instead of engine coolant temperature (ECT).
By time you reconfigure the 1999-2004 V6 to work well with the 1996-1998 electronics you will end up with almost the same motor (3.9 vs 3.8). But with the same intake so no real improvement in air flow.
At the end of the day the swap gets you a newer motor that's internally balanced that's very close to the original motor after a fair amount of work.
If the original motor is tired and in need of help it maybe wiser to rebuild the motor that you have.