I did that for a little while.. I admit, it sounded cool, but it got somewhat bothersome after a while.. Interior noise was way too high, and it vibrated the floorboard. It's a much rougher ride.
It's not going to help performance any because the exhaust is already as narror as it's going to get at that point. Now, were you to install headers and a 3" Y-pipe, then have that going through the stock 2"-ish pipes, you'd notice a gain if you took the exhaust off.
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89 iroc-z 305 tbi
k&n filtercharger, open element air filter. nuffin' else | 
