The Evolution performance exhaust, made of our proprietary titanium, is an even better match for the GT-R, complementing its race-inspired looks. Substantial work by the R&D team was required to achieve impressive horsepower and torque output increase over stock, with gains being realized at the redline and throughout the entire rpm range. There are substantial reductions in weight achieved through careful design and the use of light titanium. The power-to-weight ratio improves on both fronts: power increase and weight reduction. The GT-R deserves a great sound and the Akrapovic Evolution system delivers it: deep, loud, and aggressive but without droning. Complete the look with a set of four exquisite tailpipes in carbon fibre.THIS PRODUCT DOES NOT MEET EMISSION COMPLIANCE REQUIREMENTS FOR STREET OR HIGHWAY USE.When replacing the stock exhaust that includes valves, then the ECU remapping is mandatory!