The paper presents the results of calculation research use two-phase characteristics of the fuel in the fourcycle diesel with supercharging. The object of research - automotive diesel JAMZ-238NB. Technique is described calculating the heat in the two-phase injection. The results of an experiment conducted to obtain the real parameters worker process and configuration of the complex calculation programs. The calculated research has shown sufficient efficacy of the two-phase fuel to reduce toxicity and increase the efficiency of diesel engines for example, JAMZ-238NB.