35mm is the inner diameter of the exhaust stub, so the area is 962mm, that means the port in the cylinder can flow more and is a funnel at this point. Which is what I was starting to notice while cleaning it up.
When do you stop making the port larger?
figure that if you increase the ID of the exhaust port to 39mm (so increase it 2 mm all around), that puts you at 1194 mm^2, which is pretty much a match for area. I didn't measure it exactly, but I definitely took a a couple mm off the walls of the exhaust port on the VBB's Pinasco when I opened the port up, although I didn't specifically calculate and set a target.