I need "L" section piston rings for a highly stressed air cooled 2 stroke race kart engine. I have searched the world over with NO LUCK finding one that is of high enough quality in the size range required. (56.5mm bore) So I set out to manufacture a few of them myself....... I thought that the hard part would be creating the proper ring profile. But that seems to be very doable. The problem is selecting a material that will retain its spring tension at temp. From information found on line I am advised to look for a material with about 18%cr with substantial amounts of Nickel and or cobalt. That criteria falls into the "super alloys"... The first "super alloy" I tried was "nitronic 60". It was chosen with the hope that it could be used without heatreating. But after a short run time the rings lose to much of their free gap (spring tension). The next consideration is stainless 330, alloy 25 or inconol 625. I can only find these materials in round bar which makes the pricing rather steep using it for piston rings. Hoping someone here can point me in the right direction before I get in a lot of material I can't use. The cylinder liner is centrifugally cast steel. And if the ring material chosen is not compatible with the liner, I can have the face of it hard chrome plated. Thanks for any input.......2005bully