Oh dear God! 318 stroker

Then there is the 360 100 thou overbore at 4.100.
Offset grind the 4.000 to 4.030 and 'hey presto' its 426!!!

Just got to find some 4.100 pistons lol:thumbsup:
Better be sonic checking the cylinder walls first. Could end up with a tin foil thickness in one spot that breaks at first start. Years ago my dad related he and his buddies bored a block to fit I think it was Cadillac pistons. That is what happened to them, got through cam breakin but blew first time the driver lailed the throttle in gear.