Largest displacement of a factory 440 block?

The only stroked 440 i've been involved with was to 500ci so I probably can't help. Hughes engines can probably help though or at least give some advice on going further, I think they only go to 500 cubes as well but who knows. Personally if I were going above 500 I'd at least get the mains cross bolted and add a girdle cause I've been on the loosing end of a 440 that had to many horses pulled off the old crank and it wasn't pretty. :evil2: