Qsteel, sae 1008 through 1022, 13.810 in. Od, 0.020in. Thk, 3.380 in. Diameter center hole, eight 0.468 in. Diameter holes equally spaced on 13.125 in. Diameter bolt circle, six 9.531 in. Diameter holes equally spaced on 4.400 in. Diameter bolt circle