i just received my set of pacesetter long tubes and im planning on putting on magnaflow cats and two dynomax bullet mufflers. right now i just have cat back exhaust but i want to make it true duals and throw an x pipe in there. my question is if the end of my headers that will connect to the cats is 2.5", is there any way i can connect two cats that are 2.25" and have a tight seal? i would like to run 2.25" due to the tubing after my current muffler

 

you could run 2.5 cats then reduce the pipe size. you can get reducers through summit.