We got to looking at the stock pistons and rings we had. I just happen to say something about the way you should install the rings then he realized that he put the middle rings upside down. Motors running strong and no smoke at all with 2,000 miles on it but I want to know about the longtivity of the rings? The only difference is the little grove on one side and smooth on the other barly noticable thats how he did this.