02flhtci, 95 big bore, worked over heads, 21g andrews cams, power commander, ,with V&H slip 4" slash cut round slip ons. had dyno and custom mapping done, 80hp 90tq no back firing on decel with the custom mapping.
Just installed a full sac dual exhaust got the popping back on the decel,

got a set of fatshots ST. tried them with the 12discs the amount that comes with the fatshots, way to quiet (sounded like the bike had asthma) got recommendation to try the open end caps or more discs, tried the racing cone shape end caps (had to buy these) tried with 8 discs, to loud, then 6, then 4, all still to loud, if I remove the discs and go with just the racing end cap what would be the point of the fatshots????

(I spent more money) got a 12 pack of discs, then went to 18 discs per side, still fairly quiet and have the understanding that anything more than 18 discs will flow more than the core??? and I would also have to buy longer screws?

No way did 6 or 4 discs with racing end caps come even close to sounding anything like the 18 discs with the closed end caps, the 18 and closed caps is a lot quieter (the racing end caps are supposed to be 10-12discs worth) ...Did I do something wrong????

I should have done a little more research to find out how many discs I may of
needed, of course ST will be glad to sell you more discs or the racing end caps (cone shaped) and screws and the grease etc....so far very dissatisfied with the fatshots trying to find a happy medium? and sick of spending money.
Any suggestions??? seriously thinking of pulling them and going with the V&H monster ovals.