These valve spring kits are designed for a wide range of applications. They may be used in a mildly tuned Street Cruiser, a highly tuned roaring Strip Burner and anything in between. Springs may be used for cams up to .690" lift and spring pressure can be set from 180 to 230 pounds. These Kibblewhite Precision Machining designed and manufactured spring kits are made of extra Heavy-Duty race quality and lightweight materials, making them very suitable for any High Performance engine. Kits include 4 pairs of 15-degree machined heat treated steel keepers (except for 2005 to present Twin Cam, these use the stock keepers), 4 double racing valve springs, 4 hard anodized lower collars except for Shovelheads, these use the stock lower collars), and 4 either heat treated steel retainers, or 7075-T6 hard anodized aluminum alloy retainers or titanium retainers. Kits for V-Rod include 8 double racing valve springs, 8 heat treated steel lower collars, and 8 titanium retainers. Dependent on the application shims to set the installed spring height may be included.