The 848's are getting scarce enough that it might be necessary to go back to the old-school way to increase compression- - - -mill the older head .090" and recess the intake valves the same distance to keep them from hitting the pistons. 848's were made standard equipment on passenger cars around 1957 or so, I think. I'm sure one of the part number gurus will be around shortly with more accurate information. I don't think one particular stovebolt head is worse about cracking than another- - - -they all have a habit of doing it.
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!