Need a replacement catalytic converter for your 1980 Mercury Marquis? MagnaFlow offers high-quality catalytic converters engineered for 1980 Mercury Marquis sub-models and engine sizes. We combine efficient design and state-of-the-art manufacturing to meet or exceed required emissions standards. Select your 1980 Mercury Marquis requirements and state vehicle registration to buy the best Marquis catalytic converter online that fits your '80 Marquis and meets your state’s emissions compliance.