This kit is a cat back kit and retains the factory catylitic converters. This mod requires no tuning whatsoever. If you were to remove the cats which I recommend against, then tuning would be required and even them passing emissions standards would be extremely difficult if not impossible.Dumb question but, since the only cars I've modded didn't have a cat, I'll ask it.
I assume the computer will sense the cat is missing so is there a mod to prevent the check engine light from coming on or to pass smog? Back in the day it was a pain to reinstall stuff to pass so I'm assuming there is an easier work around these days.
I did GTS and folks were talking about a sensor mod but I didn't see it in the write up.