How big is the stock tubing for the exh. Just wondering.

thanks for the replies...I'm just going to replace the cat with a cherry bomb and strait pipe the rest, but I'll keep it 2.5 inches. Any guesses on how much peak HP all this extra flow will add? Keep in mind my intake is already done.

Stock exhaust diameter is 2.5". NA models should stay that way, SC'd can go up to 3" (especially if they've done their intake).

With the intake done, I think you could expect 10-15 hp from a performance exhaust system. Not positive, but I've heard that somewhere, and it sounds reasonable. It'* different from model to model. All depends on how the manufacturer choked off the exhaust.