I'll throw in my 2 cents on this topic. I flow bench tested an 848 head with various CNC machined alterations and sadly none of them made an appreciable improvement in flow. The reasons for this can explained in
this picture. The short side radius is only 1/8" and as flow is increased the charge bounces off the back wall and becomes disorganized. Enlarging the runner from the intake (as documented by Frank McGurk)actually sacrificed velocity and was detrimental to flow numbers. The guy that did the testing for me had considerable racing engine experience and tried putting a clay "wedge" on the back wall of the port to help direct flow but it didn't really help due to the overall poor shape.
