Turbocharger is a device increases IC engine performance and improves fuel economics by driven extra compressed air into the engine. In the present study, the turbine blades of turbocharger are modified to be thinner. The performance of the modified turbocharger is compared with that of the original turbocharger. The results show that the brake specific fuel consumption is improved as the rotation speed is less than 3000rpm. In addition, the boost threshold of the modified turbocharger is also reduced to lower rpm.