I wish I had numbers for you from a set of 906 heads I have on a shelf In my house. I bought them used from a friend in the 1980’s and they have a little what looks like splash zone in the roof. Pretty sure they came from out west but like I said my buddy bought them. I went 9.82 with them in my 1974 duster back in 1991 on super stock springs. They had 3/8 valves in them with I think 2.14 valves in them. Now that I have a seat machine I may take them off my shelf for some upgrades one of these days.