Ok, i have a catback exhaust system with 2.5" piping on my 99 prelude. The muffler was annoying sounding so i ordered an APEXI N1 universal muffler. When i finally recieved it they had sent me the Turbo muffler with 2.75" piping. I was just wondering if this mufler would decrease power since i dont have a turbo, and if it would sound crappy, etc. Thanks for any help.

Well technically with just the muffler you wont really get any power all you will get is just sound. You may lose a little backpressure but only minor not enuf to slow ya down the only thing is that the bigger muffler will give it and even raspier noise to it

you're probally be makin less power then the correct sized muffler. is it just the muffler or with the piping? if its with the pipes then you will be losing some air velocity through the pipes.

You won't lose anything noticeable at all.. like 0.5hp in the lower rpms.