A method of forming a bowl in a top surface of a piston for an internal combustion engine includes machining the top surface of the piston to form a spherical depression in the top surface wherein the top surface comprises a dome prior to the machining and a center of the bowl is displaced from a center of the piston by at least one-quarter of a diameter of the piston. In one embodiment, the method includes machining recesses in the top surface aligned, respectively, with intake valves, an exhaust valve, and spark plug when installed. Because the bowl is smooth and shallow, the surface area of the combustion chamber is less than with a deeper bowl of complicated shape. Lowering surface area in the combustion chamber leads to improved fuel economy.