this my final report of my project, I need to get the research part done as it on contents table, then we will move to the result and discussion in anther order so just do the research AN INVESTIGATION INTO THE SOURCES OF SOUND FROM 3-CYLINDER VEHICLES AND THEIR CONTRIBUTION TO DRIVE-BY NOISE this the topic and the resaerch areas are 3-cylinder engine development in trems of noise refinement 2 The sourece of noise (just intake , exhust , and tires nosie) 2 .