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Ever since mainstreaming of automobiles, engineers are focusing on making the vehicles better by means of making them more efficient, powerful and less polluting. In this study, venues of improving low end torque via improvement in volumetric efficiency as well as proper selection of turbochargers is done. An in-depth analysis of gas dynamics with respect to valve timing is studied along with the AVL Boost 1D simulation. It was found that volumetric efficiency starts to improve when there is a reduction in exhaust - exhaust valve overlap. There is an improvement found in the fresh air ratio (lambda) as the residual gas content is reduced. After the selection of valve timing, turbocharger optimization is done with comparison between two turbine sizes. Along with turbocharger comparison, technology comparison is also done namely between normal electronic VGT (Variable Geometry Turbo) (bigger turbine) and electronic VGT coupled with waste gate (smaller turbine).

During the cold start conditions engine must overcome higher friction loss, at the cost of fuel penalty till the optimum temperatures are reached in coolant and lubrication circuits. The lower thermal capacity of the lubrication oil (with respect to the coolant) inverses the relation of viscosity with temperature, improves engine thermal efficiency benefit. Engine oil takes full NEDC test cycle duration to reach 90°C. This leads to higher friction loss throughout the test cycle, contributing a significant increase in fuel consumption. Increasing oil temperature reduces viscosity, thereby reducing the engine friction. This helps to identify the focus for thermal management in the direction of speeding up the temperature rise during a cold engine starting. This work aims at the study and experiment of an exhaust recovery mechanism to improve the NEDC fuel economy.