In my experience swapping out exhaust on two FLHTs I have found the large muffler tube with large baffles to be not as loud as the small muffler tube with smaller baffles and I have no idea why.
I couldn't begin to say how many large tube mufflers I installed on my 02 FLHTUCI which didn't have the sound of the small tube/1.75 baffles in the Samson Rolled Thunder. I didn't want to repeat this expensive muffler swapping on the 09 CUSE4 but it seems I am.
I have totally removed the CAT and tried the 2.25 Fullsac baffles with packing in the stock mufflers. They are not as loud across all of the throttle ranges as the Jackpot Dyno Tuned Mufflers. The best sounding are the Samson Rolled Thunder 1.75 baffles but the small tube just doesn't look as good.
I have always heard the smaller baffles makes less noise so why do the Sampsons sound the best? I am wondering if swapping out the baffles in the Fullsac mufflers might match the sound of the Sampsons?
It sounds ridiculous but if I could squeeze the Sampson muffler tube into the larger stock muffler I think I would be happy!