A method of increasing the performance of an internal combustion (IC) engine without any major investment or mechanical parts which requires additional energy to operate is investigated. A convergent-divergent induction nozzle is tested in order to increase the air flow into the engine which in tern may increase the overall performance. The induction system was applied to the air before the throttle body of a four-cylinder, four-stroke diesel engine connected to an engine dynamometer with airflow and pressure drop measurement facilities. The measurement was done at an engine speed of about 3500 rpm. The results are compared against the performance characteristics of a plain (without nozzle) induction system. Investigations were also done to find out the most suitable material for the nozzle itself taking into consideration the factors influencing its conditions such as vibrations and temperature variations. The results of test show an increase in air flow into the engine, an increase in brake power as well as in mechanical efficiency which demonstrate that the nozzle type induction can improve the performance of an IC engine.