The FSI (port fuel injection) engine is a “direct in-cylinder injection engine” that uses stratified combustion technology.
In a traditional engine, a fuel injector injects gasoline into intake manifold, a mixture of gasoline and air, and then enters cylinder for combustion. Gasoline and air are evenly mixed in intake manifold, so air-fuel ratio (air-fuel ratio) should reach theoretical value (14.7:1) for best power and economy. But this state is difficult to achieve, and this problem is also a problem that traditional motors cannot solve.
The FSI kernel solves this problem very well. The FSI engine uses a stratified fuel injection mode at medium and low speeds, at which time throttle is in a half-open state, and piston top is given a special shape, when compression process approaches end, a small amount of fuel is injected directly into cylinder. Combustion in this form is sufficient , and combustion in other parts of cylinder is not very violent, so cylinder can be made thinner, which reduces engine weight, saves costs, and reduces fuel consumption.
FSI engine benefits:
Firstly, lower fuel consumption and improved emissions, and secondly, reduced engine weight, which saves fuel and reduces operating costs. Disadvantages of FSI engine: Due to high compression ratio, it makes high demands on fuel. According to prevailing domestic situation, it is necessary to use 98 gasoline.
The TSI engine uses two superchargers to achieve goal of small displacement, high power and low fuel consumption.
T means Turbo, S means Supercharge, so this engine is equipped with exhaust gas turbocharger + supercharger. Therefore, it can achieve large power with small displacement, which is a powerful, low speed and torque motor.
Advantages of TSI engine: little loss of power, the possibility of obtaining more power with a small displacement.
Disadvantages of TSI engine: Compared to FSI engine, it does not have a stratified combustion function, and technical content is much lower.
TFSI engine is also a turbocharged direct injection engine, four letters means turbocharged stratified fuel injection, it can be said that it is a combination of FSI engine and TSI engine.
Its T is same as TSI's T, which stands for turbo technology, and its S is same as FSI's S, which stands for "layered", not TSI's boost value. The TFSI engine has both turbine and stratified combustion, which can be said to combine advantages of FSI engine and TSI engine.
The advantages of TFSI engine: combining advantages of FSI and TSI
Disadvantages of TFSI engine: higher quality gasoline is also required