I cannot find any ring gap specs for an s50. Any experts out there with GOOD info that I can trust. Looking for all three gaps, I have the three piece oil rings. They were ordered from Hastings by piston size by my machinist due to BMW's price of Almost $600 for stock ones. I was considering going with M20 specs but I'm hesitant. Digger, Mr325, MysterE, Jlevie, help needed.