The main features of the exhaust manifold are to reduce exhaust resistance and avoid mutual interference between cylinders. 12

The exhaust manifold is a component connected to the engine cylinder block. Its main function is to collect the exhaust from each cylinder and introduce it into the exhaust manifold. Through the design of the pipeline with branches, the exhaust resistance is minimized and the interference between cylinders is avoided. This design is to prevent the mutual interference between different cylinders when the exhaust is too concentrated, that is, when a cylinder is exhausted, it just hits the exhaust gas that has not been exhausted from other cylinders, thereby increasing the exhaust resistance and reducing the output power of the engine. In order to solve this problem, the design of the exhaust manifold usually separates the exhaust of each cylinder as much as possible, with one branch for each cylinder, or one branch for two cylinders, and each branch is as long as possible and independently formed to reduce the mutual influence of gases in different pipes.

In addition, the shape and material of the exhaust manifold are also determined according to the performance and working environment of the engine. For example, the exhaust manifold of high-performance vehicles is mostly made of stainless steel to provide better heat resistance and mechanical properties. The shapes of the exhaust manifolds are different, but the lengths are similar, mainly to ensure the stability of the turbocharger's exhaust gas collection and reuse when the engine discharges the exhaust gas. This design not only takes into account the engine's power performance, but also the overall efficiency and durability of the exhaust system.

In summary, the design and material selection of the exhaust manifold are intended to optimize the engine's performance and durability while ensuring the effective operation of the exhaust system.