we are running a noram ge drum clutch on an unrestriced flathead/sportsman class. weight is 350. we had two different clutches start to lock up on us with two different drums. both were heavy shoes. we still have one left and it is a light shoe. my question is, what color springs do i need for it? i know engangement should be around 4k. the last one that burnt up had dark green springs. any help would be greatly appreciated. thanks.