Exhaust manifold intended for: Audi 1.8T K04 Seat 1.8T K04 VW 1.8T K04 Dimensions: Outlet diameter (internal): 40mm Exhaust duct diameter (internal): 35mm TurboWorks exhaust manifold is made of 100% stainless steel. engine, the exhaust manifold should be replaced at the very beginning, because the exhaust gases, pressed from the cylinder, go to the exhaust manifold, which is part of the engine body, then they are directed to the first section of the exhaust pipe, then to the muffler, or several silencers arranged in series, and then to the exhaust part of the exhaust pipe. In some versions of the engine, it may be necessary to grind the flange to fit the kink on the head. The kit includes a set of gaskets. The product comes with a 24-month warranty. We also offer lambda probe adapters that eliminate errors Catalytic converter is also available for the exhaust manifolds accessories: & nbsp