Lowers your GT500 approximately 1.5-inches;165 lb/inch front linear rate spring;160 lb/inch rear dual-rate spring;Designed for drag race applications;Manufactured from chrome silicon high-tensile spring wire;Cold wound on a CNC Coiling Machine to exact specifications;Lifetime warranty against spring sag;Stress-relieved at 750 degrees F;Shot-peened;Computer tested for accurate height and spring rate;Made in the U.S.A.