i removed my cat, went 2.5" piping from the midpipe to the tail with a flowmaster 40 series. i had the muffler welder after the cat it sounded good but when i removed the cat and put a straight pipe in its place.... WOW what a difference in throatiness muchhh deeper tone and more raspy. best part i have passed emissions the past two times i have went

reasoning is cause wranglers do not have an o2 sensor after/before the cat. they are up at the headers. for cars 95' and above all they do is stick the obd2 sensor in the port, see if you throw a CEL for emissions and if theres no code or engine light your golden

have fun and it sounds awesome.
PS... get a snorkel instead of a CAI. thats actually functional, wont get water in the intake unless your going threw the ocean and its about the same price.