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 : cca985-12 Description : Dual Valve Spring Assemblies; 12 Pieces Title : 985-12 Valve Springs, for 984-973 Coil Bind Height(in) : 1.15 Installed Height(in) : 1.75 Outside Diameter(in) : 1.43 Installed Pressure(lbs) : 164 Open Pressure(lbs) : 331 Camshaft Type : Mechanical Spring Rate(lbs/in) : 333 Spring Type : Double Position : N/A Inside Diameter(in) : 0.7 Open Height(in) : 1.25 Engine Components::Valve Springs, Retainers