Ok, I've run a few different types of exhaust combos on an 88GT with a 347 stroker.
First is:
Unequal length Mac shorties with bbk catted h-pipe and 2 chamber flowmasters.
This was very muffled sounding. My guess is the cats ruin the sound.

Second is:
Equal length BBK shorties with BBK catless x-pipe and 2 chamber flowmasters.
This was my best combo that I liked, and sounded MEAN. Real hollow sounding.

Third is:
BBK Longtubes with custom made offroad x-pipe and 2 chamber flowmasters.
I'm not so happy with the longtube sound.

Fourth is:
BBK Longtubes with BBK catted h-pipe and 2 chamber flowmasters.
Another really muffled combo.

My real question is, what difference could I face between an offroad bassani xpipe and bassani mufflers with the stock manifolds on the 2003 Cobra, and my second (best) combo of Equal length BBK shorties with BBK catless x-pipe and 2 chamber flowmasters? Will these differ much?