I am young and want me E to be a little bit louder. I am not talking stereo system wise, more along the lines of the motor or exhaust. I have a K&N SRI and that makes it a little bit louder, but what would be the next step? Adding a full exhaust system is expensive ($500 at least is what it seems like), but what about just a muffler? I want it to be deep and throaty, but no drone at highway speeds. Is there any other way to get a little more growl out of the E?