custom cat back

There ya go.

Or just get a custom 2.5" or 3" or whatevers most efficient on those motors (look it up on the forums) and have a resonator and muffler welded in. ZZP makes a whisper resonator that quiets down a lot of the rasp and sound yet still flows like an open pipe.

Like I said, think of what the purpose of the exhaust is for. On a daily driver there is no reason to have a loud raspy exhaust like that.