Exhaust/Mufflers

[nsb29]

I have the cast manifold that came with the motor which is from a Pontiac G8 I believe similar to the Camaro cast manifolds from there is 2 1/2 inch exhaust back to the mufflers and then exit behind the rear wheels I did not use an H Or X pipe driving down the highway it really isn’t that loud but going through the gears it’s louder than I wanted I am considering installing two small glass packs behind the mufflers in a straight area about a foot and a half from the end I also wondered if it was because I did not install an H or X pipe ????? I also wondered if it was the brand I bought and maybe I should have bought magnaflows but if you’re having the same problem that’s obviously not it if you figure out something before I do post it I’ll do the same