318 head porting for the average joe

The set sure need some rounding/smoothing..............
Never done a 302 so i can't say. But that sure look like a lot of material to remove there. and why is it there. has to have some purpose! would have been way easier to have made the mold smooth there then add that bump, must has a reason, but i have no idea.

K, here is a couple question for you.
What is IN the combustion chamber? And, what is the Material that is in the exh port sealing off the air ports.(small holes that are drilled in the exh gasket surface that go into the port.