mufflers only vs. cat back
just starting work on my car, and new to the site... was wondering, if my goal is simply to add some HP and TQ(300 and 340 first goal) and not increased noise level(some would be OK, tone more important) to my car, why can't i just add some decent mufflers as opposed to a full cat back system? the pipes are exactly the same size.
bear in mind, i cannot (or rather, do not want to) go catless with an o/r mid, as i'm in NY. will mufflers alone, like the FM 44's, help the cause? i'd rather put the money elsewhere if i'm not gonna gain much power.
i am expecting my cai and tuner, thinking about a TB(no more than 70 or 75mm) and maybe plenum, new s-t shifter, u-p drive(maybe), and rear gears.
help enlighten me if you can? thanks-