How can you tell if its stroked then? Other than splitting cases?

I cant see any identifying marks on the crank looking thru the timing hole or cam bearing hole...

 

Place the crankshaft at TDC of one of the cylinders. Remember they are 45deg apart so make sure you measure the perpendicular from the crank pin to the cylinder base. You can use center of piston pin or top of piston, just make sure everything is lined up.

Make a mark or measure the distance from your reference point, rotate the crank 180deg to BDC(again perpendicular to the cylinder base) and take a second measurement at the same reference point, subtract the two and you will have the stroke.

 

Stroker cylinders are the same height as stock ones, the pistons are shorter, so that at TDC they reach the same high point in the cylinders as stock ones. My stroker engine used my stock cylinders, so there is no need to change them. Those do look odd, I've never seen anything like it before.

 

Sputhe Engineering has done some unique stuff over the years. I believe they brand their parts. But you might send them a pic and ask if they've got any ideas about the origin of your cylinders.

Alan