Manley LS and LT Valve Spring Kits provide a complete, engineered solution, ensuring seamless compatibility for higher-lift camshafts and eliminating concerns with mismatched components.NexTek? Valve Springs are manufactured from "super clean" Hi-Tensile Chrome Silicon steel and shot-peened to MIL spec for maximum fatigue life. Spring No. 221436-167? Titanium Retainer CAD designed for ultimate reduction in mass without sacrificing strength. Retainer No. 23623-16 (Std. Installed Height)I.D. Valve Spring Locator is CNC machined, heat treated, and black oxide finished. Locator No. 42334-16 (.505" ID)7? Machined Valve Locks use the highest quality steel alloy and are heat treated and black oxide finished. For 8mm (.3135") valve stem. Lock No. 13098-16Viton Valve Stem Seals offer exceptional resistance to heat, chemicals, and oils. Seal No. 24042-16Note: Max. lift figures above may vary depending upon the cylinder head and installed height.