This paper deals with the heat transfer enhancement due to groove formation in a metallic tube. A detailed computational fluid dynamics (CFD) analysis was performed on helical groove tubes with three geometries (obtained from a published article) to validate the results, and three other geometries, randomly selected, with variable pitch length apart from experiment. The range of Reynolds number was from 4000 to 10,000. Performance criterion through CFD was based on the heat transfer via Nusselt number as well as the friction factor. The friction factor and Nusselt number comparison with experimental data was found to be in good agreement with the experimental data, with an average deviation of 2 and 7%, respectively. Numerical experimentation was extended by examining the performance of three more tubes of varying pitch lengths. The new tubes had pitch length of 51 mm (GT02), 102 mm (GT04) and 152 mm (GT06). The performance was evaluated in terms of thermal enhancement factor. It was found that the all tubes have enhancement factor greater than unity which means that tubes are efficient in terms of heat transfer. Among the tubes studied, the maximum thermal enhancement factor was also obtained for GT02 (51 mm pitch length).