A gas turbo set including a first turbine, a second turbine, and a combustion chamber connected between the first and second turbines and operated by auto-ignition is provided. The turbines and the combustion chamber are located on a common shaft that may be rotated about an axis. To increase the efficiency of the gas turbo set, the outer periphery of the second turbine is at a greater distance from the axis than that of the first turbine, leading to a reduction in the size and/or the number of turbine blades.