+1Or just buy a proper decat that has been designed for this purpose and to flow the exhaust gases correctly
Agreed. Turbulance in your exhaust gas flow is far from "smooth" and "free flowing". A good decat pipe is best, trust me, I've had all three . That said, a gutted cat will flow better than stock.its exactly because of that mate, its not a smooth flow, stuff gets caught up and turbalance from stuff going to and from the out side
If you look inside a gutted cat I dont see how a specially made decat would flow any better, the cat is bloody big.