What does the letter on the car's butt mean?

The owners are driving cars every day. Many consumers can also identify various models through the tail design. What do you mean by the suffix letters on certain parts of the rear? Let Xiao Bian lead everyone to a big literacy and look at our car in another angle.

Supercharged engine

Type 1: TSI (common to Shanghai Volkswagen, FAW-Volkswagen, Skoda)

The meaning of VW's TSI is not the same at home and abroad. It means “Twincharger Stratified ion” in foreign countries. It refers to the dual boost (turbo and supercharged) stratified injection technology. In China, T stands for turbocharging, Si stands for direct fuel injection, not the abbreviation of T and FSI, and there is no fuel stratified injection technology because domestic fuel quality is generally not enough to meet the requirements of stratified injection.

At home, we often see different TSI logos. All red, "SI" is red, and only "I" is red. However, everyone should not misunderstand that their skills are different. This is just to distinguish different displacements.

Type II: TFSI

TFSI is a turbo fuel direct injection engine, which is a combination of FSI engine and turbocharger. Turbocharger + FSI. Its T is the same as T in TSI, which means turbocharged technology. The latter FSI is the Fuel Stratified ion, and S means “layered”. The TFSI engine is both stratified and turbocharged and is an upgraded version of the TSI engine.

Type 3: TDI

TDI is the abbreviation of English Turbo Direct ion, which means turbocharged direct injection diesel engine. In order to solve the inherent deficiency of SDI (Natural Aspirated Diesel Engine), people have installed turbocharger on the diesel engine, so that the intake pressure is greatly increased, the compression ratio is generally more than 10, so that the speed can be very low A large amount of torque is achieved, and due to more complete combustion, the content of harmful particles in the emissions is also greatly reduced.

Naturally aspirated engine

Type 1: CGI/CDI (common in Mercedes-Benz cars)

The engine CGI technology is an in-cylinder direct injection technology developed by Mercedes-Benz. The oil supply action is completely independent of the door and the piston system, and the ECU has more control over it. The mixing ratio of lean burning to more than traditional jet theory can be realized. At steady-state or low-load conditions, engines with direct-injection design can enter the Ultra lean mode.

Under this setting, the engine can only inhale air during the intake stroke. As for the fuel injector, fuel is only supplied during the compression stroke to achieve a saving effect. According to actual tests, the ratio of oil and gas with a maximum energy ratio of 1:65 can be quite impressive, and the overall power curve can maintain a relatively high degree of smoothness. CDI is the diesel version of the technology.

Type II: VVT/CVVT/VVT-I/MIVEC/VTEC/i-VTEC (common in Korean cars)

The principle of Variable Valve Timing (VVT) is to adjust the amount of intake (exhaust), and the valve opening and closing time and angle according to the operating conditions of the engine, so that the amount of air entering the air can be optimized and improved. Combustion efficiency. The advantage is fuel economy, the power up ratio is large and the disadvantage is that the mid-cycle speed torque is insufficient.

Currently, Honda's VTEC, i-VTEC, Toyota's VVT-i, Nissan's CVVT, Mitsubishi's MIVEC, Suzuki's VVT, Hyundai's VVT, Kia's CVVT, Jianghuai's VVT, and Great Wall's VVT are also gradually used. In general, it is actually a technique with different names. However, some models only have variable valve technology and no timing technology. Although they are more fuel-efficient than normal engines, they still can't catch up with timing technology engines.

Green engine

Type 1: Hybrid

A hybrid electric vehicle (HEV) refers to a vehicle that is equipped with two kinds of power sources at the same time: a heat power source (produced by a conventional gasoline engine or diesel engine) and an electric power source (battery and motor). By using a motor in a hybrid vehicle, the power system can be flexibly regulated according to the actual operating conditions of the entire vehicle, while the engine is maintained in an area where the overall performance is optimum, thereby reducing fuel consumption and emissions. BMW's ActiveHybr also belongs to this type of system.

Type II: DM

DM is an abbreviation for Dual Mode. It is a combination of pure electric vehicle (EV) and hybrid (HEV) technology. The DM dual-mode electric vehicle uses an electric vehicle system and a hybrid power system. It is a technology that combines the control of the engine and the motor's two hybrid forces, enabling a variety of energy supplements that can be charged and refueled. (Note: Such signs are common on both sides of the car and on the front of the car.)

Drive System

Type one: Quattro

At the heart of the Quattro full-time four-wheel drive is the Torsen Central Differential, which adjusts the distribution of front and rear axle forces faster than any electronic control technology. The EDL (Electronic Differential Lock) transmits excess power to the wheels when necessary to enhance grip. When the wheels are idle or not in contact with the ground, these wasted driving forces are transmitted to the wheels that can be stressed. Once there is a difference in the speed of the front and rear axles caused by external conditions, Torsen will automatically transmit most of the energy to the working axle with no loss, automatically optimizing and distributing the power of the four wheels.

Twenty-five years ago, Audi engineers set a milestone in drive technology with quattro full-time four-wheel drive.