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 : cca933-12 Description : Hi-Tech Oval Track Valve Springs; 12 Pieces Title : 933-12 Valve Springs, 1.550" NASCAR Outside Diameter(in) : 1.55 Open Pressure(lbs) : 494 Position : N/A Camshaft Type : Mechanical Coil Bind Height(in) : 1.2 Open Height(in) : 1.3 Installed Pressure(lbs) : 176 Inside Diameter(in) : 0.73 Spring Type : Double Installed Height(in) : 1.95 Spring Rate(lbs/in) : 490 Engine Components::Valve Springs, Retainers