look the only reason for a resonator is if you take your cat off. someone mentioned you need a resonator a long time ago on these forums, not telling anyone that you only need it when your cat is removed!! now when people talk about exhausts i always hear about the damn resonator. you dont need it!!! if you get custom piping from the cat back you wont need a resonator. and if you keep your stock pipes it will be fine but the they somehow have to be fitted at the end to match the input on the muffler. and i think that defeats the pupose of a new exhaust. go with the extra 50 bucks or whatever it takes to get the custom piping. its really cheap.