Need a replacement catalytic converter for your 1991 Oldsmobile Cutlass Supreme? MagnaFlow offers high-quality catalytic converters engineered for 1991 Oldsmobile Cutlass Supreme sub-models and engine sizes. We combine efficient design and state-of-the-art manufacturing to meet or exceed required emissions standards. Select your 1991 Oldsmobile Cutlass Supreme requirements and state vehicle registration to buy the best Cutlass Supreme catalytic converter online that fits your '91 Cutlass Supreme and meets your state’s emissions compliance.