yep thats what Neil from troyer said. He said there should not be any problems and my tune from them should fix that. Yes they do come with high flow cats. Whats wierd is the next day when driving i felt like the car had ALOT more power going over inclines and the freeways. The thing is sooooo loud now to a point where its kind of funny. Picture my 5 foot asian wife driving the truck that makes most car alarms go off. The sound is like a mixture of a modded mustang and a modded dogde. ALOT more drone now though while cruising usually around 1800 rpm.

 

Sound clippppppppppppppppppppppp!