According to whether the air intake system adopts the supercharging method: it can be divided into supercharged (forced intake) and non-supercharged (naturally aspirated). The supercharger is used to increase the intake pressure and increase the intake density to supercharge the internal combustion engine, which is beneficial to improve the power of the internal combustion engine. The intake air carried out in a state close to the atmosphere is a non-supercharged internal combustion engine or a naturally aspirated internal combustion engine;
Classification by cooling method: Internal combustion engines can be divided into water-cooled engines and air-cooled engines according to different cooling methods. The water-cooled engine uses the cooling liquid circulating in the cylinder block and the cylinder head cooling water jacket as the cooling medium for cooling; while the air-cooled engine uses the air flowing between the cylinder block and the outer surface fins of the cylinder head as the cooling medium. cooled. The water-cooled engine has uniform cooling, reliable operation and good cooling effect, and is widely used in modern vehicle engines.