ok, you need a bigger case for the main muffler, find a 24" 11x5 range with the internal pipe making the S bend, offset to offset, this will give the sound notes more to bounce off with the extra angles, the louvered MBRP will help sound some if you install it backwards, with the exhaust flowing into the openings of the them, wont help much with drone

its about surface area and contact time, a second muffler will help the first or one large

a 4.8 with a 12" louvered glasspack installed correctly will be louder than a 6.0 same muffler installed backwards......from idle through about 3K

 

Not for those wanting a sleeper but it does sound pretty sweet...
4" factory resonator off a Dodge Ram Mega Cab Diesel, Pacesetter LTs, 3" Y-pipe, no cats all the way back into the 4" resonator dumped. Sounds killer, but way too loud in the cab, much louder than the 3" Dynomax bullet(22"? whichever the longer case is) that was on it before. Probably gonna toss the bullet back on before the 4" resonator.


Knocked the rust off it and paint it black...