What is the function of the engine intake manifold?

[MacGraham]

The function of the engine intake manifold is to distribute the combustible mixture supplied by the carburetor to each cylinder, collect the exhaust gases after the operation of each cylinder, and deliver them to the exhaust pipe and muffler before being discharged into the atmosphere. The intake manifold is usually made of cast iron, but it can also be cast from aluminum alloy. These two materials can be cast as one piece or separately. The intake manifold is fixed to the cylinder block or cylinder head with studs, and asbestos gaskets are installed at the joint surfaces to prevent air leakage. The intake manifold is located between the throttle valve and the engine intake valve. It is called a manifold because after air enters the throttle valve, it passes through the manifold buffer system, and the air flow path diverges here, corresponding to the number of engine cylinders. For example, a four-cylinder engine has four paths, and a five-cylinder engine has five paths, directing air into each cylinder respectively.