The exhaust heat exchange coefficient in a pipe of internal combustion engine has been measured with a specific exhaust-air heat exchanger. It''s installed on the exhaust line of IC engine. The Nusselt-Reyonlds correlation has been developed and compared to the steady-state conditions known as Colburn''s correlation. The Convective Augmentation Factor (CAF) is approximately 2 at low Reynolds number and 1 at high Reynolds number. The technology of EGR cooler and the exhaust-coolant heat exchanger for improving the thermal comfort have been shown. A vehicle equipped with a direct-injection turbo diesel engine has been tested in the climatic wind tunnel. The heat performance in the passenger compartment will be presented.