Wich diameter for a custom B-Pipe. From header to exaust.
I have a DC Sports 4-2-1 stainless steel and Ractive loop exaust.

I have a friend that can make me one in stainless steel.

Now the question is wich piping diameter, the best one for high revs gain ?

Thanks.

 

If your going n/a 2.5 but the rest of your setup is 2.25 so there wouldn't be any gains.

 

The same diameter as your header collector and the muffler. Which I think is 2.25".