ok,

i have two assembled pistons in my hand (from two different manufacturers).

one piston is assembled with the piston pin hole (opening) facing the exhaust side

the other piston is assembled with the piston pin hole (opening) facing the carb side

is there a right / wrong way?

the manufacturer exploded diagrams do not put any real emphasis on it, and there is no detail or mention of it.

some say to face the opening of of the piston pin towards the carb so it carrys the oil better

some say to face it towards to exhaust port to eliminate build up.

what are you thoughts?

if it makes no difference, why is one end of the piston pin opened, and the other closed?