Need a replacement catalytic converter for your 1981 Dodge Diplomat? MagnaFlow offers high-quality catalytic converters engineered for 1981 Dodge Diplomat 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 Dodge Diplomat requirements and state vehicle registration to buy the best Diplomat catalytic converter online that fits your '81 Diplomat and meets your state’s emissions compliance.