Dual Valve Springs from COMP Cams are manufactured from Super Clean wire and subject to extensive quality control testing to deliver a valve spring assembly with superior strength, durability and valve train stability, no matter what the application. The dual spring design creates a stronger valve spring that can easily handle the increased lift found in extreme stress applications. COMP Cams Dual Valve Springs exceed the expectations of today’s engine builders and racers. PartNumber : cca927-1 Description : Hi-Tech Oval Track Valve Springs; Single Piece Title : 927-1 Valve Spring, NASCAR California Proposition 65 : WARNING: Cancer and Reproductive Harm P65Warnings.ca.gov Coil Bind Height : 1.175 Compatible .570" Guide Diameter Spring Seat : 4780-1 Compatible .630" Guide Diameter Spring Seat : 4780-1 Compatible Retainer : 732-1 Compatible Shims : 4757 Compatible Spring Cup (O.D. Locator) : 4700-1 Damper : Yes Inner Spring Inside Diameter : 0.721 Number of Springs : 2 Outer Spring Inside Diameter : 1.117 Outer Spring Outside Diameter : 1.551 Seat Height : 1.95 Seat Pressure : 201 Spring Rate : 499 Valve Spring Series : Race Endurance Open Height(in) : 1.25 Outside Diameter(in) : 1.539 Coil Bind Height(in) : 1.175 Camshaft Type : Hydraulic Inside Diameter(in) : 0.731 Open Pressure(lbs) : 543 Spring Type : Double Installed Height(in) : 1.95 Installed Pressure(lbs) : 197 Position : N/A Spring Rate(lbs/in) : 494 Engine Components::Valve Springs, Retainers