It might handle an 80 overbore, but be very sure you have a very good condition cooling system. Those cylinder walls will be pretty thin. If you're determined to keep using that particular block, sleeve all the cylinders back to standard bore, using sleeves with 3/32" wall thickness.
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!