[A Snake]

Good question FFR

There are several combinations that will cause this as well as a deck height issue.

It boils down to wrist pin location for the different stroke/piston combinations. IF you can, get the number off a piston and check it with the manufacturer to see what it is supposed to fit.

A little unlikely but not impossible, is that someone had the crank ground with an offset to use smaller rod journals and or change the stroke and the pistons are not the problem at all. If you can, accurately, check the stroke with a dial indicator and/or a precision caliper (they have a depth rod). It should be 3.73" (less deck material removal and bearing clearance) from deck to piston top at bottom dead center.

Hope this helps.

Al