Fusion excitation functions are measured for the system ⁶Li + ²⁸Si using the characteristic gamma-ray method, encompassing both the sub-barrier and above-barrier regions, viz, E_lab = 7-24MeV. Two separate experiments were performed, one for the above-barrier region (E_lab = 11-24MeV) and another for the below-barrier region (E_lab = 7-10MeV). The results were compared with our previously measured fusion cross-section for the ⁶Li + ²⁸Si system. We observed the enhancement of the fusion cross-section at sub-barrier regions for both ⁶Li  and ⁷Li, but the yield was substantially larger for ⁶Li. However, for well-above-barrier regions, a similar type of suppression was identified for both the systems.