Exhaust fab

[snapper]

Turbosports forum ran a header calculation program for me
The manifold I had was pretty good for primary diameter and bore, I just needed to make the collector wider and have the silencer can made with a specific collector to can distance.
Running big valve head, bike carbs and RL31 cam
Does it make a difference, we will find out when I rolling road it
I though if I'm doing the exhaust I would do what I can to optimise it