H-Pipe Replacement on Nismo

FL 4Motion

You are correct. I made a thread a while back where I measured our oem nismo exhaust at different points and the H pipe was necked down to 2.1" and the post H pipe pipes to the muffleer were 2.4".

so basically, other than the H pipe, we have a 2 1/2" exhaust and the cats and the H pipe are the restriction.

That said, you'll save some considerable weight too, switching out the oem nismo exhaust for something like the FI cbe. That's what ultimately swayed me into getting the FI CBE vs. having a shop fab up and x pipe for me. I wanted to benefit form the weight savings too.