The basic parameters of the engine

The basic parameters of the engine number of cylinders The number of cylinders commonly used in automotive engines is 3, 4, 5, 6, and 8 cylinders. Three-cylinder engines with a displacement of less than one liter are commonly used, 2.5-liter engines are generally four-cylinder engines, three-litre engines are generally six-cylinder, four-litre is eight-cylinder, and 5.5-liter or higher is a twelve-cylinder engine. In general, under the same cylinder diameter, the more the number of cylinders, the greater the displacement, the higher the power; Under the same displacement, the more the number of cylinders, the smaller the bore diameter, the speed can be increased to obtain a larger power.

Arrangement of cylinders Generally, cylinders of engines below 5 cylinders are often arranged in an inline manner, and a few 6-cylinder engines are also inline. The cylinder block of the in-line engine is lined up in a straight line. The structure of the cylinder block, cylinder head and crankshaft is simple, the manufacturing cost is low, the low-speed torque characteristics are good, the fuel consumption is small, the size is compact, and the application is extensive. The disadvantage is that the power is low. In-line 6 cylinders have good dynamic balance and relatively low vibration. Most of the 6- to 12-cylinder engines are arranged in a V-shape. The V-shaped, ie, cylinders, are arranged in four columns at offset angles. The bodies are compact, and the V-shaped engine is small in length and height, making it very convenient to arrange. V8 engine structure is very complex, manufacturing costs are high, so less used, V12 engine is too large and heavy, only a very few high-end cars.

The number of valves made in China is mostly based on two valves per cylinder, that is, one intake valve and one exhaust valve; foreign sedan engines commonly use four-valve per cylinder structure, that is, two intake valves and two exhaust valves, which improve the intake and output. Exhaust efficiency; some foreign companies have begun to use five valves per cylinder structure, that is, three intake valves, two exhaust valves, the main role is to increase the intake air, so that combustion is more thorough. The number of valves is not as good as possible. The 5-valve does improve the intake efficiency, but the structure is extremely complicated, processing is difficult, and there are few adoptions. The new Jetta King of domestic production adopts a five-valve engine.

Displacement cylinder working volume refers to the gas volume swept by the piston from top dead center to bottom dead center, also known as the single cylinder displacement, it depends on the bore and piston stroke. The engine displacement is the sum of the working volumes of each cylinder and is generally expressed in liters (L). Engine displacement is one of the most important structural parameters. It is more representative of the size of the engine than the bore diameter and the number of cylinders. Many engine indicators are closely related to the displacement.

Maximum output power The maximum output power is generally expressed in horses (ps) or kilowatts (kw). The output power of the engine has a great relationship with the rotation speed. With the increase of the rotation speed, the power of the engine also increases accordingly, but after a certain rotation speed, the power tends to decrease. The maximum output power is generally expressed in revolutions per minute (r/min) in the automobile instruction, such as 100 ps/5000 r/min, that is, the maximum output power is 100 hp at 5,000 rpm.

Maximum Torque The torque output from the crankshaft side of the engine. The torque is expressed in N. m/r/min, the maximum torque generally occurs in the middle and low speed range of the engine. As the speed increases, the torque will drop instead. Of course, the choices must be weighed against how to use them rationally and not wasting existing ones. For example, it is necessary to open air conditioners in winter and summer in Beijing. When selecting the engine power, it must be taken into consideration that it should not be too small. It is only necessary to pick up large-horsepower engines when commuting to and from the city loop. As far as possible, economically and rationally selecting the engine.

5V

V is the initial letter of the English "valve" (value). The traditional car engine cylinder generally adopts 4 valve structures, ie, 2 intake valves and 2 exhaust valves, which ensure that the intake and exhaust are full and effective, which is conducive to the increase of the engine speed, thus achieving the maximum power of the engine. 5 valve technology has been widely used in foreign car companies, recently listed in China's "Bora" has adopted 5 valve technology, that is, 3 intake valves, 2 exhaust valves. Volkswagen AG is the leader in 5-valve applications.

ABS

It is an abbreviation of "anti-lock break system" in English and is translated into "anti-lock break system" in Chinese. It is a kind of safe brake control system with anti-skid, anti-locking and other advantages. Without an ABS system installed, when it comes to an emergency situation, it is too late to brake slowly and can only be trampled to death. At this time, the wheel is easily locked, and the sprint inertia of the vehicle can cause dangerous conditions such as side slip, deviation, and uncontrolled direction. The car with ABS, when the wheel is about to reach the next lock point, the brake can play 60 to 120 times in one second, which is equivalent to stop braking, relax, that is similar to the mechanical "point brake." Therefore, it is possible to avoid the loss of control of the direction and the side slip of the wheels during emergency braking, so that the wheels are not locked when the brakes are applied, the tires do not rub against the ground at one point, and the frictional force is increased, so that the braking efficiency can reach over 90%.

GPS

It is the abbreviation of Global Postioning System. The main function of GPS is anti-theft function, anti-robbery function and navigation function.