Exhaust on a Civic.

[4jacks]

Whether 3" was too big was my kinda hidden question.
I've heard that the theory " An exhuast needs Backpressure" is just crap.
If this is true then the best pipe size would kinda cap off, like you would get the same advantage out of a 4" as you would a 3" if you really only needed 2.75"

A larger exhuast pipe can't lose potention gain , can it ?????

I guess it would all boiler down to the "Back Pressure" Idea.

Plus my exhaust has a 2.5" inlet, I was just trying to prevent as much back pressure as possible.

Another thing is that the 2.5" pipe was a BIG increase over the 2.25" ....