Abstract: Disclosed is a centrifugal molten metal pump assembly and associated system for controlled delivery of molten metal to molds. The pump assembly comprises a shaft, an impeller coupled to the shaft, a controller to control a rotational speed of the impeller according to a programmable fill profile while delivering the molten metal to the mold. In some embodiments, the pump assembly further comprises a throttle to manipulate a flow rate or pressure of the molten metal relative to a rotational speed of the impeller. The associated system comprises a melting furnace and one or more holding furnaces, each holding furnace including at least one pump assembly therein. Each holding furnace may be of an open configuration to allow for uninterrupted flow of the molten metal from the melting furnace. The system may provide controlled delivery of the molten metal to the mold at a desired flow rate or pressure.