What size valve? I would put money on it not being the chamber. I would put my money on the issue being from the middle of the short turn to the vary edge of your valve job. Including from side to side.
That port is a 2.02 but i have ports from 1.88,192 and 2.00. They were all 1.88 stock tulip valves. 192, and 200 and 2.02 are nail heads (2.02s cut down)
It vary well could be, as i had no clue about off set of Bowl and cyl wall side.