Hey Darren, thanks for the heads up on not cutting out the rear cats. What option do I have? Am I able to replace all 4 with 2 Hi-flow Maggie Cats? And this Y pipe you speak of, the flowmaster that I purchased is a 3'' inlet. Better performance running the y pipe versuses the stock pipe?

 

Possibly, check with your emissions testing and ask what your converter options are, I think its alright as long as 4 hi-flows go back in it.

Yes, If I were you I would certainly buy the Magnaflow Y pipe converter, run 3" intermediate pipe all the way to the muffler, it will sound so much better, and perform much better since its not all 2.5" When you think of it, dual 2.5" in to 2.5" single exit Y pipe, how healthy is that for performance? None its restrictive, but if it flows out 3" it will have great velocity.