Quote:

In a shop manual it says to spread the gaps at 1/3
apart...
to the guys that say they move around.... WHY do they
move.... how come the ring gaps arent always lined up
when you pull it apart




Just statistically speaking, it would be rare to have the gaps lined up when you pull any one piston. Depending on resolution, there maybe 1/20 chance of them being "lined up" (to one's eye) and 19/20 that they aren't.

I don't know why they spin, but there seem to be so many forces and movements going on in there, and how they interact with the bore/hone etc., that it would be interesting to know why people think they don't spin.