If you do anything beyond your 3.4/bolt on setup (big cam business, intercooled, etc) and intend on driving it a lot, you better start saving for a built trans now. The stock drive chain is pretty weak, 4th gear has a tendency to disappear in the pre-2003 vehicles, the clutch packs get worn, etc... There's a couple guys on the forum who have managed to get away with their stock trans for some time, but it's not mainstream.
This is what happens when you go fast:
http://www.grandprixforums.net/threa...s-broken-parts!!!
Of course, even this is infinitely cheaper than buying a new "sports car" with comparable wheel hp numbers off the lot... Just be prepared to break things if you want to go fast in a car that frankly, wasn't designed to go fast.