Hydrogen fueled engines are known for several advantages, among which is the very low concentration of pollutants in the exhaust gases compared to internal combustion engines using traditional or other alternative fuels. Hydrogen driven vehicles thus reduce both local as well as global emissions. Furthermore, because of the wide flammability limits and the high flame propagation speed of hydrogen, a hydrogen fueled engine is capable of very lean combustion, allowing power regulation by varying the richness of the air-fuel mixture. Thus, better efficiency is reached because of the possibility to work without throttle valves. The Laboratory of Transport Technology (Ghent University) converted a GM/Crusader VS SI engine for hydrogen use. A sequential timed multipoint injection system was implemented. The corresponding electronic management system was used to optimise the engine parameters (ignition timing, injection timing and duration) and to program several corrections in the case of changing working conditions (fuel pressure and temperature, inlet combustion air pressure and temperature, etc.). Finally, the goal of the development is discussed: the building-in of the engine in a city bus, with its conditions of sufficient power (90 kW) and torque output (300 N m), together with extreme low emission levels and backfire-safe operation.