I figured I'd post this in case anyone is on the fence about buying stifflers products. I know most say if it worked MM would do it etc. I've yet to be dissapointed by anything I've got from stifflers. As far as I'm aware still the only one selling chassis stiffening parts based on test results of twisting mustang chassis on a jig. All I can say is I immediately felt a difference during acceleration. Before the car would sort of twist upward kind of like the motion of a wave, and honestly it was something I just never noticed until today. The car is just on point it feels solid, hit the gas pedal and it just goes no twist present. Much less nose dive during hard braking and it feels really good on the bends. One of the best suspension mods I've done yet.