hey i got tired of searching for my answer b/c i got like 1,000 post w/ all haveing nothing to do w/ what i looking for.
ok here it goes and i kow ya have herd it before, if i remove my cat and add a 2.5" exhuast piping from the end of the headers to the muffler, what kind of oncrease or decrease can i expect?

i have a 98 gs and i di di the same thing i have the greddy headers with a straight pipe to a flowmaster it sounds pretty shitty but i did see a gain

do you think it would sound shitty if i have a silencer or tuner on it?

i had about the same setup and added a glasspack in it and it helped out with sound alot. Gave it a more deeper tone instead of raspy sound

well i just want a some extra hp i dont care much for sound, currently my exhuast whistles after 3500 and sounds like a bumble bee.