Fuel economy is the key target and driving force for gasoline engine performance development. Based on the principle of single cylinder optimal performance, the core architecture design parameters were determined through the concept design and single cylinder engine test. Through the performance development test, the effects of port and combustion chamber system and compression ratio on the combustion efficiency were studied. The potential of pumping loss reduction was explored by using electric waste gate turbocharger system and external cooling EGR. The effects of variable volume oil pump, low tensional force piston ring on mechanical friction loss reduction were verified. A development system of fuel consumption reduction was established, which was applied in engine development projects.