i've heard different opinions about what size to run for my setup. I'm running a gsr-turbo pushing 8psi only. currently in the "open downpipe" mode but wanting to run an exhaust to get rid of that loud noise n smell!

being that im only pushin low boost, some people said i'll be ok with 2.5 piping.

But, some people prefer me to run a 3" stainless exhaust kit.

would running a 2.5 in piping cause me to lose power? if not, or would running 3" cause me to lose/gain power running at the same boost level? give me some tips :D