Graphical Abstract: The influence of added alcohols, ethanol and butanol, on the main biofuel properties, such as the specific gravity, Reid saturated vapour pressure and distillation curves have been investigated. These properties are intimately related to the fuel composition and their prediction relies on the knowledge of its components characteristics. This research proves the possibility of obtaining fuels with different levels of resistance to detonation, using gasoline with different chemical components and various fractions of alcohols.