1.) You have 17" wheels. End of story.
2.) If you're willing to waste your money, go ahead and get the ITR motor. A complete swap for an ITR will probably cost your around 6 grand. Totally not worth it.
If you're looking for relativly cheap speed, I'd say go for a simple (or relatively simple) T03/04 turbo setup. A cheap effective setup will probably end up being about 3 grand installed, and when tuned properly, can probably have you pushing 230-240 hp and running decent times at the track.
Oh yeah, for the love of God, PLEASE keep your racing to a track.