you might gain some hp, it would help alot only if, the stock cat is old and super restrictive. But straight pipe is louder.... too loud depending on muffler to go with it, but 20hp.... maybe if you consider one thing, the car is 140 stock, over years of use, and wear and tear, and a dirty clogged cat, you might be at 130, or less, with straight pipe and tune up, you might be back at a 145-150.
Im gonna stop, im just talking out my ass now.
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