360 rings. gapless?

That's backwards. Who's ring set was this? The top ring is the compression ring. The second ring's main function is scraping oil away. It doesnt do much to hold in pressure. In fact, many builders now set the second ring gap slightly larger than the top ring, because if gasses build up in between the rings, the top ring's sealing ability is compromized. Smokey Yunick knew about this in the 70s...