small block heads, 4027596 casting # any good??

Looks like the extremes of the tables on flow numbers I've seen. More or less, about the same, lets keep splitting hairs for fun!

So far, of the comparo you list, the X head has a 2.02 and the other a 1.88.
Why did you stop at .450? They will flow more past that point.
Also, what is typical?
flow to .450" becouse thats when the #'s nose over. X-heads flow right to .550" typical would be anyother LA head.