Comparison of characteristics of spark pług engines FSI, TSI/TFSI type of Volkswagen Company

The use of direct injection in spark ignition engines significantly facilitated the use of chargers in these engines. This resulted lately in the significant popularization of direct injection engines, initially freely sucking and in final result turbocharged. The greatest popularity on the market gained engines of Volkswagen Company, named FSI and TFSI / TSI. Application of Common Rail systems allowed not only improving the characteristics of the engine by increasing the accuracy in dispensing fuel into individual cylinders. The most important gain is the possibility of second injection of the fuel to the cylinder after the intake valve is closed. On the one hand it allows better control of the load in the cylinder, at first with the piston crown, and now with shaping the injection by the injector. On the other hand it allows creating a stratified mixture, at low load of the engine it reduces fuel consumption and work at high excess air ratios �� . Quickly it began to use the turbocharger in those engines due to the significant improvement in the operating characteristics of such engine. Profit from better filling of the combustion chamber can be used in different ways. On the one hand, you can replace engines naturally aspirated, with turbocharged with lower displacement, which leads to the improvement of the economics of such engine. On the other hand, after appropriate modifications to the design, you can add a charger to the naturally aspirated engine, retaining its capacity. Gains are then not only higher operating parameters, such as power and torque, but it also significantly improves the torque curve. It has big impact on the flexibility of the engine and the vehicle which is powered by it. Another gain is larger amount of work done by the engine.