Let's see. I don't honestly know if it would make any diff. havin a 3" on an n/a car. That's what I have on my gtp. It does sound better, I know that. Its louder. U prob won't notice any diff in power from cat dp to off road. I didn't have any problem gettin mine in. Its an easy swap with simple hand tools. Just get both gaskets. Their cheap. I've heard of some people not havin any problem with the o2 sensor. I just went ahead and got the simulator anyway and I haven't had any problems. And yes, if u get one of their dp's the old u-bend is now a straight pipe. Get one. Ull enjoy it
