The BTR platinum spring kit would be inducted into the LS aftermarket hall of fame if such a thing existed. Whether you're putting together a daily driver with a mild cam, a 600 hp N/A stroker, or a turbocharged 1000 hp brawler, our platinum spring kit will make sure your valves are right where your cam wants them to be at all times. They are designed to be used with stock rocker arms. This is a drop-in kit for 15° LS heads. It will also typically work with LS7 heads when used with a .030” shim (Part numbers SS030). This kit will not fit LS9 engines. See part # SK006 for LS9 heads. Kit includes: SP001-1 dual polished spring (qty 16) VL7°8MM-1 locks (qty 32) chromoly steel (SR001S-1) retainers (qty 16) Locators for stock or bronze guides (qty 16) VS LS valve seals (qty 16)