[71RoadRunner]

I've heard some V6's that sounded like V8's at an idle and it was because of a free flowing exhaust and Flowmaster mufflers. If you want to stay legal and have a V8 sound get one size larger exhaust, headers, high flow catalytic converters and Flowmaster mufflers. For best results make it a true dual exhaust, instead of a 2 into 1 into 2 like most have. The only drawback is that it may sound like a V8 when idling, but it will still sound like a V6 when you accelerate.