The differences between TSI, FSI and TFSI are as follows. All three are direct injection in the cylinder, and they all belong to Volkswagen. Lamborghini is a subsidiary of Volkswagen.

1. TSI

TSI is the abbreviation of Twincharged Stratified Injection in English, which refers to twin-charged fuel stratified injection. Supercharging uses the power of the engine itself to compress air, while turbocharging uses the exhaust gas energy in the exhaust system to drive the turbine. Turbocharging responds slowly and has hysteresis when the engine speed is low, while supercharging consumes more engine power when the engine speed is high, so using dual supercharging can complement each other's advantages.

2. FSI

FSI is the English abbreviation of Fuel Stratified Injection, which refers to an in-cylinder direct injection engine that uses fuel stratified combustion technology. The so-called stratified injection is based on direct injection technology. In short, it is to inject oil once during the intake stroke. The mixture formed at this time is very thin (25:1), and the spark plug cannot ignite, so the compression Inject oil again during the stroke. At this time, the mixer is richer (12:1) and can be ignited. After the rich mixture is ignited, the combustion quickly spreads to the outer layer. In China, due to oil quality reasons, FSI only represents direct injection in the cylinder.

3. TFSI

TFSI is the abbreviation of Turbo Fuel Stratified Injection in English, which is an FSI engine with turbocharging (T). Compared with TSI, it lacks supercharging. . However, in China, both TFSI and TSI only have two technologies, one is turbocharging and the other is direct injection in the cylinder. However, in order to stand out as more high-end than Volkswagen, Audi will slightly increase the power by a few kilowatts in tuning, creating a different illusion.

Extended information:

Cylinder direct injection (GDI) is a technology that directly injects fuel into the cylinder to mix with the intake air. The advantages are low fuel consumption, high power per liter, and a compression ratio as high as 12. Compared with ordinary engines of the same displacement, the power and torque are increased by 10%. The current disadvantage is that the components are complex and often more expensive.

The injection pressure has also been further increased, making the fuel atomization more detailed, truly achieving precise proportional control of fuel injection and mixing with the intake air, and eliminating the shortcomings of out-of-cylinder injection. At the same time, special designs such as nozzle position, spray shape, intake airflow control, and piston top shape enable oil and gas to be fully and evenly mixed in the entire cylinder, thereby allowing the fuel to be fully burned and the energy conversion efficiency to be higher. Therefore, some people think that the in-cylinder direct injection gasoline engine is a pioneering work that transplants the form of a diesel engine to a gasoline engine.

Reference: In-cylinder direct injection - Baidu Encyclopedia