The Evolution systems for the GTI retain all the exclusivity of the titanium Slip-On exhaust systems, including stunning carbon fiber tailpipes, and display further potential through additional link and down pipes made from high-grade stainless steel for even greater strength and enhanced temperature and corrosion resistance. With its sports catalytic converter, bigger tubes, and optimized gas flow and back pressure, Evolution unleashes additional power and improves the torque and responsiveness of the GTI’s four-cylinder engine. Akrapovi?’s state-of-the-art technology and innovative solutions provide an exciting exhaust system for the latest Golf GTI with even more tuning potential. Engineers have spent countless hours fine-tuning the sound too, to give you that deep sporty Akrapovi? sound throughout all revs.When installing Akrapovi? aftermarket optional down pipes with sports catalytic converters or without catalytic converters, which are developed for use on closed tracks only, remapping the ECU is mandatory. When installing Akrapovi? aftermarket exhaust system that was developed for use on closed tracks, we recommend remapping the ECU in order to prevent potential »check engine light« warning signals. THIS PRODUCT DOES NOT MEET EMISSION COMPLIANCE REQUIREMENTS FOR STREET OR HIGHWAY USE.