Experiments on ribbon-tubular car radiators with the same whole structure but different wave distance were carried out in a heat transfer wind tunnel in order to obtain the cooling water temperature and water flow at water inlet and outlet of radiator,the cooling air temperature and air flow at air inlet and outlet of radiator,the dissipated,heat,the wind resistance and water resistance and other related test data.According to the experimental data,the relations between heat dissipating capacity,wind resistance and wave distance were analyzed.The water gate location under different heat transfer conditions of radiator was discussed and the effects on heat transfer characteristics and flow characteristics were analyzed and compared.Experimental studies on the performances of double drain and single pipe belt type radiator were conducted and their resulte were contrasted.Finally,on the basis of the experimental data and analysis results,the optimization design of car radiators was presented.