I don't think the rings actually rotate per se, but they do move from the installed location......After about one hour of break-in and dyno time on my pressant race motor, I changed the
oil and filter and when I drained the
oil, I found about a quart of water in the pan, so I tore the engine down to see what the problem was.....(failed head gasket)
As I tore it down, I was very careful with everything as this was a brand new BOSS 302 block and I just knew it had a crack in it somewhere and would have to send it back to Ford. I took photos to document any and everything I did and found and what I found was a failed head gasket, causing the water in the
oil..
I also found that the rings on 4 pistons had "move/rotated" some from the original position..... I made sure checking 2 or 3 times each piston as to the location of the ring gaps before installing them in the block, the rings were put as per directions on the box (Mahle rings).....on 3 pistons the ring movement was not very much, may 20 to 30 degress at most, on the forth one, the top ring had rotated enough so that the gap was lined up with the gap of the second ring, not good..... I checked with a number of engine builders and they told me they had seen this before, kinda normal for some rings to rotate some, they all said depending on the ring type/manufacter, some rings "move" more than others.........
on other engines I've done, ring movement/rotation has been minor....
Had I not seen it myself, I would have never thought the rings would rotate....
David