I actually ran into this problem this past fall. I didn't realize they had changed when I ordered new rings. The old style pistons are a 1.0 x 1.2 x 2.8 and the new ones are 1.2 x 1.2 x 3.0. I called modern performance when I ran into this problem and they found a set on hand that would work. This was on 88mm pistons. The part number is JG1004-3465.