Abstract

This article shows an investigated research on Compressed Natural Gas (CNG) engine with a port injection when varying ignition timing. The obtained results from simulating study have indicated that both of brake thermal efficiency and torque have a similar trend when varying ignition timing. The effect of ignition timing on the value of brake thermal efficiency is stronger in comparison with torque, however, the increase in engine speed or lambda value have to adjust the ignition timing more early. To reach the maximum break torque at each engine speed, the ignition timing should be adjusted IT = 14 - 32 bTDC, and this is also basic value to design the ignition timing system using CNG engine with port injection.