What is an Exhaust Manifold?

[Brayden]

An exhaust manifold is a branched pipe system connected to the engine cylinder block, designed to collect exhaust gases from each cylinder and direct them into the main exhaust pipe. The design of the exhaust manifold must take into account engine power performance, fuel economy, emission standards, engine cost, compatibility with the vehicle's front compartment layout, and temperature distribution. Currently, the most commonly used exhaust manifolds are categorized by material and manufacturing process into cast iron manifolds and stainless steel manifolds. Key requirements for exhaust manifolds include minimizing exhaust resistance and preventing interference between cylinders. When exhaust gases are overly concentrated, interference between cylinders can occur—meaning that when one cylinder is expelling exhaust, it may encounter residual exhaust gases from another cylinder that have not been fully expelled. This increases exhaust resistance and consequently reduces the engine's output power.