"Knock the center out of the cat converter"......? Oh dear oh dear.....where do I even start to comment on the illegalities of doing that....
Last I heard, the friendly EPA officers will slap you with something like $2000 or more for running a car without a catalytic converter...could be more now. "Couldn't happen to me"? Really. My brother had his 2 year old V6 Commodore tested by a roadside test of some sort by the transport department (he's not exactly mechanically minded, so couldn't unfortunately explain to me exactly what they did... :b: ...but I assume it was some sort of basic gas analyser) and was "officially warned" that his emissions were reaching the "limit". When he commented, gobsmacked, that the car was only a couple of years old, the officer shrugged and said that not many people know that at most catalytic converters only "do thier job" for somewhere between two and six years before they should be replaced...so technically most people are driving around with illegal cat converters, and if the feds wanted to be nasty, could slap everyone with massive fines...nice. :bang:
Better off spending money on a high-flow converter and trying to keep legal....saves a lot of hassel in the long run....monetary type hassels... :embarrass