I am trying to build a Billancourt classic engine, in 1946 campain, normally 603cm3 with 49 bore and 80 stroke.
Clearly, the interface does not allow it, whenever I change bore it adjust stroke and vice versa.
Is that a new thing? I dont remember such problem in earlier versions. What am I missing here?
Bore x stroke limitations have always been there, you can try giving the engine the lowest bore possible while having the stroke you need, and then adjusting it further in the variant menu, that way you can get around the limit to some extent.