The Clapeyron equation defines the relationship between temperature and vapor pressure. If the absolute temperature graph is plotted, a straight line is obtained on the y-axis of the graph against the logarithm of the vapor pressure. Each liquid and gas-phase hydrocarbon can be determined in the graph. While plotting this graph of the benzene-toluene mixture that affects fuel performance, the pressure values of the mixture are determined by the separation of the mixture from the air. Usually, when drawing this graph, critical temperatures and pressures are essential and more pronounced in hydrocarbons where aromatic structures are rich. To determine the vapor pressure, the atmospheric pressure, such as the boiling range of the sample, must be determined depending on the liquid boiling temperature of a reflux condenser. This means that the temperature of the fuel at a vapor pressure exceeding 760 mmHg in the same graph, apart from this temperature, is estimated. The slopes of other petroleum products can determine the slope of the obtained temperature distribution. If the boiling point cannot be determined experimentally, the temperature value in the Engler distillation curve corresponding to 20% distillation can be taken. A proposed solution of the McCabe-Thiele method as an alternative to other methods for the distillation properties of the benzene and toluene mixture that affect the fuel efficiency is described in this study.