The existence of shockwaves in pneumatic valves can greatly affect their efficiency and cause damage to important parts. This study focuses on the examination of a cost-effective pneumatic directional control valve with the aim of augmenting its output mass flow rate. Emphasis is placed on scrutinizing and modifying the critical flow area to facilitate increased flow rates under specific upstream pressures while eliminating the formation of shockwaves. To achieve these objectives, numerical simulations are harnessed to accurately capture the onset of shockwave formation and elucidate the associated conditions, allowing optimizing valve's capacity without introducing the risk of shockwave occurrence. The modified valve design demonstrated the capability to eliminate shockwave formation within the valve while concurrently increasing the mass flow rate by up to 70% within the same range of inlet pressures. This novel approach holds substantial promise for enhancing system response and represents a significant contribution to the field of pneumatic control valve design.