Manley valve springs are wound from super clean alloy. Each design minimizes stress to ensure long service life with high lift camshafts. Titanium retainers are manufactured in our own double spindle CNC machines to exacting tolerances and precise installed height specifications. Valve locks are manufactured in our own Swiss turning centers with rigid control over the all-important angle to ensure precise mating with the retainer. Application: Honda S2000 F20C and F22C engines.