I installed a Vortech SQ trim on my Bullitt (sad to say it's not MPH's kit, *proceding to kicking my own @$$). I loaded up the tune and started her up. Everything seemed fine, so I shut it down to recheck everything to be sure and fired her up again and got a check engine light. I pulled the code and it's P0453. I looked it up and it seems to be an emissions issue, which would maybe explain why the RPM's take a while to drop back down to idle after I hit the throttle a bit and racked up to about 3 grand. I think the issue is in the tune since the PCM controls this. I called the company to get the tune ironed out enough to get it to a dyno tune. Come to find out the company doesn't make the tune, they have somebody else do it for them and they swear there is nothing wrong with the tune and that there is something wrong with my Bullitt. I find that odd since the car ran fine before the supercharger install. If anybody has some insight on this let me know. I still think it's in the tune. If I'm wrong then let me know. Thanks.