ORIGINAL: Red B.
...If two engines uses the same crank, the one with the shortest crankpin will have the longest stroke.
Huh??? If the cranks are the same how can the crank pin be any different one from the other? Besides, a longer crank pin just gives more bearing area, it will not affect the stroke. Stroke is controlled solely by the center to center distance of the shaft itself and the center of the crank pin.