Abstract: Sand casting remains a prevalent method for manufacturing complex metal components due to its costeffectiveness and versatility. However, optimizing the gating system, particularly through runner riser modification, is crucial for enhancing casting quality and minimizing defects. This study employs computer simulation techniques to investigate the effects of various modifications in the gating system on the solidification behavior and quality of castings. Through numerical simulations using advanced software tools, different configurations of the gating system are analyzed and compared, focusing on parameters such as flow rate, velocity distribution, and solidification patterns. The results reveal insights into the effectiveness of runner riser modification strategies in reducing defects like shrinkage and porosity, thereby improving the overall casting quality. Additionally, the study explores the trade-offs between different modification approaches in terms of cost, complexity, and performance. These findings contribute to the optimization of sand-casting processes, offering practical guidance for engineers and manufacturers aiming to enhance product quality and efficiency.