Automobile engine relies on fuel burning in the cylinder to push the piston to do work, and then it is converted into mechanical energy to drive the automobile forward. There are two kinds of automobile engines now: gasoline engine and diesel engine. The earliest automobile engine was developed at the end of 19. It is a simple single-cylinder gasoline engine, and its output power is only a few horsepower, which is equivalent to the power of ordinary motorcycles now. For example, a German named Daimler was a pioneer in manufacturing automobile engines. Later, Daimler cooperated with Ben Ci, the man who made the world's first car, and the two companies merged, resulting in the now famous "Daimler-Benz" company, referred to as Mercedes-Benz. The rise of automobile racing in the early 20th century greatly promoted the progress of engine technology. Ferrari, Jaguar, Masarati and other car factories have all made great achievements in the field of racing. At that time, large-displacement multi-cylinder automobile engines had been used in racing cars and luxury cars, but at that time, due to technical limitations, automobile engines were all in-line cylinders, which could not be too complicated, otherwise the volume would be too large and the reliability would be reduced, which greatly limited the application of high-performance engines in ordinary cars. After World War II, V-type engines began to be widely used in high-end cars, while ordinary cars still use in-line engines, with simple structure and good economy. Moreover, with the development of technology, the fuel consumption of automobiles is also decreasing. In order to achieve better comfort, durability and performance, the exhaust capacity of ordinary economical automobile engines is also increasing.
The two most basic parameters to measure the engine performance index are the number of cylinders and the working volume of cylinders, that is, the commonly used displacement. Generally speaking, the more cylinders an engine has, the greater its displacement and the better its performance, and the number of cylinders is closely related to its displacement. Generally, engines with large displacement will have more cylinders. At present, the number of cylinders of most automobile engines in the world is between 4- 12, and the displacement is between 1-6 liters. At present, most cars are equipped with gasoline engines.