BMW S62 Valve Spring & Retainer Kit Our valve spring and retainer packages are specifically computer designed to ensure   wire stress levels do not overpass the limits of stress defined in the diagrams of fatigue   for long durability under extreme conditions. We also check valve springs with our tester   to ensure that all valve springs fall into the correct specifications. The titanium retainers   included are manufactured with high quality military grade titanium alloy and CNC   machined for a tight fit to ensure durability and minimize the possibility of failure. Price: $749.00