The new sharp air intake pipe has an extra tube.

An intake manifold and an exhaust manifold.

The function of intake manifold is to distribute the combustible mixture supplied by carburetor to each cylinder. The function of the exhaust manifold is to collect the exhaust gas discharged from each cylinder, send it to the exhaust pipe and muffler, and then discharge it into the atmosphere.

Air enters the throttle valve, and after passing through the manifold buffer system, the air flow channel is "divergent" here, corresponding to the number of cylinders of the engine, for example, four for a four-cylinder engine and five for a five-cylinder engine, and air is introduced into each cylinder respectively. For a naturally aspirated engine, because the intake manifold is located behind the throttle, when the throttle opening of the engine is small, enough air cannot be sucked into the cylinder, which will lead to a high vacuum degree of the manifold.