LS 660 Lift Dual Valve Spring Kit - Factory LS Casting Cylinder Head - Integrated Seat Seal

Dual Spring Kit for Factory GM Casting Cylinder. This kit is for a factory casting LS1, LS2, LS3, L92 with an OE style valve guide.  Designed for 0.500 valve guide utilizing the factory 8mm valve and valve locks. Specs: Rated Valve Lift 0.660 inches Installed Height 1.800 @ 166 lbs Spring Rate: 403#/in Solid Height 1.015 Spring OD 1.310" Spring ID 0.680" Kit includes: Dual Valve Springs Titanium Retainers Integrated Spring Seat with Valve Stem Seal 8mm Valve Locks Kit Details: Manufactured in the USA Premium Chrome Silicon Vanadium Spring Wire Polished Isotropic Super Finishing & Cryo Treated Titanium 6AL4V Grade 5 titanium retainers Machined & Hardened and Black Oxide Precision Spring Seats