Depending on your engine and type of vehicle, the exhaust manifold can either be a set of pipes or it can be a cast iron manifold assembly. Essentially the exhaust manifold takes the burned exhaust gases from the engine's cylinders and ejects the gas through the exhaust system and out through the car's tail pipe. The exhaust manifold gasket seals the surface of the exhaust manifold to the surface of the cylinder head, preventing leaks in the system. Over time, the constant expansion and contraction of the components (caused by constant heating and cooling in the engine), may cause the gasket to leak. These leaks can be hazardous as hot exhaust gases escape and can damage other components in the engine compartment. A leaky exhaust manifold gasket can also impact engine performance. So replace your gasket and regain back lost performance. Replace for 92-95 BMW 320i 92-95 BMW 325i / 325is 96-99 BMW 328i / 328is 98-99 BMW 323i / 323is 94-99 BMW M3 98-01 BMW Z3 Roadster L6 99-01 BMW 528i 328i 323i 323is 323Ci L6 Fits Header Model HDS-E36, HDS-E463S