Description: Performance Valve Springs - GEN III HEMI® (5.7L/6.4L) : Made from the same high-strength material as the valve springs found in the Dodge Viper, the DC Performance Valve Spring was designed for high lift camshaft profiles (up to 0.625” lift) such as the Mopar® Performance 5.7L Cam (part number P5160018). This spring will work with the factory seats, retainers, and locks and require no shims or machining of the cylinder head (Shims required for 6.4L application). Sold individually.