Need a replacement catalytic converter for your 1981 Porsche 928? MagnaFlow offers high-quality catalytic converters engineered for 1981 Porsche 928 sub-models and engine sizes. We combine efficient design and state-of-the-art manufacturing to meet or exceed required emissions standards. Select your 1981 Porsche 928 requirements and state vehicle registration to buy the best 928 catalytic converter online that fits your '81 928 and meets your state’s emissions compliance.