Comparison of measured drive torque and average friction torque at cam/follower interface for various commercially available engine oils of the same SAE rating (10W-40)

Abstract

In recent times, automobile scientists have focused a lot upon the fuel economy and energy conservation in motor vehicles. The search for alternate fuels and the minimization of thermal and mechanical losses in motor engines has been a major topic of research for the past several decades. In an automobile, one of the most complicated systems in terms of mechanical losses is the engine valve train. Several theoretical and experimental models have been used to calculate the losses in engine valve train and the effect of various engine parameters on the frictional losses. The work presented in this article focuses upon the drive and friction torque values for four different commercially available oils of the same grade i.e., 10W-40. These oils are Shell, Castrol, Kixx and ZIC. The tests are carried out on a Suzuki swift RS413 gasoline engine cylinder head. The variation in drive and friction torques with oil temperature and camshaft speed is presented. The results show the comparisons of these four oils for the drive and friction torque values and based on these results, conclusions are given regarding the best oil in terms of friction performance of the given engine valve train. It is thus concluded in this thesis that Kixx is the oil with the least value of average friction torque for the given experimental conditions and is therefore the best one among the four oils compared.