Picture of 340/360 head porting....Mistakes?

Do you now have the die grinder and flow bench closer to each other?

If you’re still in the R&D mode, you could just start in on another cylinder, do what seems like a straightforward normal port job on it...... flow it before and after...... maybe a couple tests of specific changes along the way...... see how it compares to the one with all the mud in it.