In order to reduce emissions, size and manufacturing cost, integrated exhaust manifold become popular in gasoline engine, especially in three-cylinder engine. Moreover, due to shorter length, lighter weight, and less component connections, the exhaust manifold and hot end durability will improve apparently. In this work, an advanced cylinder head with integrated exhaust manifold is in adopted in one three-cylinder turbo engine. Because of this integration characteristic, the gas retain in cylinder head longer and the temperature reach higher level than normal cylinder head, which will cause thermal fatigue failure more easily. To validate the exhaust manifold and hot end durability, series simulation and test validation work have been done. Firstly, overall steady state and transient temperature simulation was done for global model. The global model include cylinder head, block, turbocharger, and catalyst components. For turbocharger, in order to simulate the inlet turbulent flow and 3d rotation, a code was compiled to define this 3d rotation. In this code, the inlet boundary was defined by turbine blade’s rotational velocity, direction and angle. Secondly, based on temperature prediction, thermal modal, high cycle fatigue and low cycle fatigue analysis were done in sequence. According to LCF analysis, one location inside cylinder head was found not fulfill the life cycle target. Sub model was constructed to optimize this area for saving time. To validate the temperature distribution, 9 thermocouples were installed to test the hot end surface and gas temperature. To validate the thermal modal analysis, 7 3-direction acceleration sensors were used to test the vibration performance and corresponding engine speed. Temperature results error for most points is within 10% and modal results error is 6%. Finally, no crack failure was found inside the cylinder head and hot end after engine durability test, which also prove the LCF and HCF results indirectly.