Many years ago I bought a Jaguar XK140MC that had had higher compression pistons
retrofitted to it. Shortly after the purchase, it starting burning a lot of oil and running rather poor. I tore it down to find the PO had installed the new pistons using the type of
retainers you show in the photo. The retainers had eaten out the retainer boss, came loose and deeply gouged the cylinder walls. Had to overbore the block and install new pistons. To sum it up DON'T even think of ever using that type piston pin retainer!!
