Unless I do not fully understanding your question; the serpentine belt drives the accessories; smog pump, PS pump, AC, alternator, and the water pump, from the crank pulley, externally. Your car has an internal timing chain that articulates the cam shaft via a set of gears; one on the crank, and one on the cam. A broken serpentine belt SHOULD have no effect on the valves or any other internal engine components, even in an interference engine set up.