Hello, I have a really simple question. I own a 2008 Ve Hsv LS2 and it has only 64,000 km on it. I just my installed XForce 3 inch Cat-Back System. I would like to remove my catalytic converters. I know it's illegal to do that, but the question is Would my engine breathe better than before when I remove the catalytic converters? Would the fuel economy be better or worst? My car has two catalytic converters. Thanks.