Experimental studies have been carried out on isothermal pressure drop and convective heat transfer to servotherm medium grade oil in laminar flow in one smooth tube and seven wire coil-inserted tubes of varying wire diameter and pitch of wire coil. The performance of these wire coil inserted tubes has been evaluated by two different criteria based on the objective of either maximizing heat transfer rate or minimizing exchanger size. The results indicated that as much as fourfold improvement can be obtained in laminar flow heat transfer coefficient using these tubes.