An actuated valve having a rotatable cam that controls an opening and closing disc and stop members for the cam, the cam having a notch that allows the cam to be stopped between fully open and fully closed, and an adjustable member on the stop member that corresponds with the notch that allows the cam to be rotated to the fully open or fully closed position. A method of thermally cracking at least one of whole crude oil and natural gas condensate using the actuated value.