Abstract: On the basis of the establishment of onedimensional simulation model for the engine, engine simulation software AVL BOOST was applied to simulate the effects of different intake manifold pipe lengths and diameters on engine performance. The results show that the impact of pipe length and diameter on the engine torque and volumetric efficiency is significant. It provides a theoretical basis for further development and testing to solve the problem with the effects of the intake manifold pipe length and diameter on engine performance.

Key words: engine performance; intake manifold; pipe length; diameter;simulation model