A window balance system includes a mounting bracket configured to be secured to a window jamb, a shoe body and a coil spring movably coupling the mounting bracket to the shoe body. The window balance system also includes an engagement member extending from at least one of the mounting bracket and the shoe body, wherein the engagement member includes at least one resilient arm having a pawl extending therefrom. The window balance system further includes a receiving member defined in at least the other one of the mounting bracket and the shoe body, wherein the receiving member includes at least one rack having at least one tooth extending therefrom such that the pawl is engageable with the rack.