Need a replacement catalytic converter for your 1990 Audi 90 Quattro? MagnaFlow offers high-quality catalytic converters engineered for 1990 Audi 90 Quattro sub-models and engine sizes. We combine efficient design and state-of-the-art manufacturing to meet or exceed required emissions standards. Select your 1990 Audi 90 Quattro requirements and state vehicle registration to buy the best 90 Quattro catalytic converter online that fits your '90 90 Quattro and meets your state’s emissions compliance.