Hi, there is a local manufacturer for an exhaust in my city which makes a pretty nice looking exhaust system; however, the exhaust is 3.0" diameter. The Y-pipe comes in 2 versions, either 2.5" or 3.0". What is stock? 2.25 or 2.5?
My concern is, will there be a performance decrease due to the larger diameter if I run a full 3.0" catback for my NA setup? Or, will there be a worser decrease in performance if I get the 2.5" y-pipe and then 3.0" exhaust; I have a feeling that could potentially cause bad flow characteristics? I don't have any plans to go turbo, although that would be quite awesome.
Please advise thanks!