Influence of Fuel Injection Timing Over the Performances of a Direct Injection Spark Ignition Engine

The paper presents an analysis of the influence of the most important factors that affect the working process of a direct injection spark ignition engine, especially the injection timing.

In the first part of the paper we study the engine's constructive solution and the changes in the engine's performances induced by the alteration of the compression ratio. This phase allowed us to choose the most appropriate variant.

In the second part we study the influence of the injection timing over the engine's performances, for two different compression ratios and two injection rates.

The most significant results are emphasized using the engine's speed characteristics, determined on the test bed.