sstill.........I simply want a larger ledge for any spent exhaust to get caught as it is trying to be sucked back in to the Head (reversion).......
This is known as a pressure difference between the evacuated cylinder and the exhaust manifold. Suction can cause it, but the pressure difference is a stronger influence.
.....To npccpartman I am not port matching as you can see.That is an attempt to improve flow. I am trying to improve the intake fuel/air cleanliness for a more efficient burn, limiting any spent exhaust from being sucked back into the head....
Improving your flow, evacuates the cylinder more efficiently not only improves your cylinder contamination situation, but, will allow a fresher charge to burn more completely, inturn make more power. Turbulent flow restricts power and hinders complete combustion to put it very simple.
Have you touched anything else besides the manifolds?