Need a replacement catalytic converter for your 2005 Porsche Boxster? MagnaFlow offers high-quality catalytic converters engineered for 2005 Porsche Boxster sub-models and engine sizes. We combine efficient design and state-of-the-art manufacturing to meet or exceed required emissions standards. Select your 2005 Porsche Boxster requirements and state vehicle registration to buy the best Boxster catalytic converter online that fits your '05 Boxster and meets your state’s emissions compliance.