Best bore-stroke ratio?

[Higheta]

I know there is a great well of accumulated wisdom here, and I would like your views on a somewhat theoretical as well as practical question--

What is the best ratio of bore to stroke, and why? Some stationary engines have B/S < .30. Some high-speed engines have B/S > 1.

 

[NormPeterson]

High volumetric efficiency in a NA engine at extreme rpm levels means large valves and ports, which have to all be physically fitted in the head within the cylindrical projection of the bore (along with the spark plug, water jacketing, attachment bolts/studs, oil passages, etc., while leaving enough metal to keep all those holes separate in service).

Norm