An exhaust manifold gasket seals the exhaust manifold to the cylinder head. On V6 and V8 engines, there are two exhaust manifolds and therefore require two manifold gaskets. An exhaust manifold gasket seals the connection between the manifold and cylinder head. This prevents exhaust leakage out of the connection and also ensures that all exhaust gas will flow through the catalytic converter for treatment. Flange and ring gaskets seal other connection points in the exhaust system, such as between the exhaust pipe and exhaust manifold.
There are several types of gaskets that connect the exhaust pipe to the manifold. One is a flat surface gasket. Another type uses a ball and socket with springs to maintain pressure. This type allows some flexibility without breakage of the seal or the manifold. A third type is the full ball connector type, which also allows a little flexibility.