[stratplaya06]

First get rid of that resonator, that should solve your problem w/o affecting the emissions equipment. With that said, it won't be a huge amount louder and you may find that catless downpipes (and even leaving the stock resonator in with those new downpipes, given that w/o a resonator you will hear some rasp) are necessary to give the desired effect. The O2 sensors can be sim'd very easily and most tunes now will remove the CEL (even though some won't be emissions compliant, the wire-in solutions like the BMS dpfix are OBDII test compliant).