At the same time, the improvement of gas exchange processes is an effective way to improve the specific performance of diesel engines. The article presents an analysis of the effect of cross-profiling of the intake pipeline of a diesel engine on its consumption characteristics and power based on experimental studies. The article describes experimental stands and measuring instruments. Modification of the intake system consisted in the use of an intake pipe with square and triangular sections. The article presents data on the flow characteristics through the intake systems of a piston engine model and the power characteristics of a diesel engine with different modifications of the intake pipe. It was found that the use of profiled pipes caused an increase in air flow through the engine intake system in the range of 5-17 % compared to the basic configuration. It was revealed that there was an increase in diesel power by 3-15 % when using profiled pipes in the intake system compared to the basic modification. The data obtained are useful for the modernization of the intake systems of existing engines and the development of new diesels with promising technical and economic indicators.