if you really want loud and dont mind the drone(since you got flows, and its not loud enough, i dont think it will be a problem hehe)
look into the SLP loud mouth systems ( i cant remember if 1 or 2 is louder)
that or just go straight pipes from the x pipe back and slap some tips on at the end.
or you can get some e-cutouts
those are probably the loudest methods for this car. i think there is also a thread on this page(maybe page 2) right now about the "loudest" exhaust for the charger, check that out
