Crane Offers Several Different Single Spring Designs To Suit a Wide Variety Of Applications. They Are Available In Popular Diameters For Both Hydraulic and Mechanical ("Flat Tappet") Lifter Camshafts. Several Single Springs With Flat Dampers Are Also Available For Stock Diameter, Small-Block Chevy V-8 Applications. These Include Part No. 99849-16, 99848-16, and The New 99846-16, Designed For Use Where Rules Require a Stock Diameter Valve Spring. The 99846-16 Springs Are Made From H-11 Tool Steel and Provide Open Pressures Of Up To 350 Lbs. At 1. 175" Open Height. These "Stock Diameter" Springs For Small-Block Chevys Can Be Installed In Stock Spring Pockets Without Machining Or Removal Of The Cylinder Heads. Stock Spring Retainers Can Be Used, But We Recommend Our Crane Steel Retainers and Machined Steel Valve Locks For Maximum Strength. The 99846-16 Spring Is Engineered To Handle Up To . 585" Gross Valve Lift For Hot Street Or Rules-Restricted Oval Track Racing Cams.Pit Stop USA offers Crane Crane Single Valve Springs (16) - 1.500" O.D. - 412 lbs. Rate - 1.000" Coil Bind Height 99835-16 at low everyday prices. Be sure to check out all of our products from Crane Cams including Crane Cams Single Valve Springs.