Ford Racing 2015-2016 Mustang Performance Pack 6 Piston Front Brake Upgrade Kitmountune engineers worked exclusively with Eibach to develop a spring set that would specially meet their requirements. Our goal was to enhance and optimize the handling of the Focus ST while not overpowering the original shock absorber. We wanted the car to handle better on the track and ride comfortably on the freeways of Los Angeles. We also demanded advanced ride quality that is only offered by a true progressive rate spring. The outcome of