From what I've been told, Reinhart is coming out with a "custom" header pipe set up for the Challengers. No idea about a release date. I also heard that the "suitcase" underneath the Challenger is both a catalyst AND resonator. I have to believe that PI did a lot of engineering on this unit to create the optimum blend of performance, weight, sound and keeping "big Brother" happy. I'm not doing anything with that section of my exhaust until it can be PROVEN that performance and sound will not suffer. The good thing here....at least with this model year is that the sensors are BEFORE this unit, which means anything you do from that point back should not be "linked" to the ECU. Once these manufacturers install sensors AFTER the cat/resonator, like in our current, modern day road vehicles, you're going to need some sophisticated tuning to eliminate any CE lights. Just my thoughts for what they are worth!!!!