This paper studies the enhancement of maximum lift coefficient and cruise efficiency using Co-Flow Jet (CFJ) active flow control airfoils. For potential flows, the maximum lift coefficient limit is derived as CLmax = 2π(1+t/c) for any airfoil with thickness of t=c. The present study indicates that the CFJ active flow control airfoil is able to achieve the maximum lift coefficient that far exceeds the theoretical limit. It is named super-lift coefficient. The research is based on validated CFD simulation, which employs 2D RANS solver with Spalart-Allmaras(S-A) turbulence model, 5th order WENO scheme for the inviscid fluxes, and 4th order central differencing for the viscous terms. The momentum coefficient Cµ studied is from 0.02 to 0.60 and the angle of attack (AoA) is from 0° to 74°.