The .675" Lift Conical Spring Kit with Titanium Retainers for GM LT1/LS7 Applications features a smaller diameter in the upper half to reduce active mass. This reduction in mass, along with the progressive frequency created by the conical shape, dampens coil oscillations better than any other spring design. These improvements in dynamic stability allow for the use of more aggressive Camshafts and an increase in RPM limit speed. Finally, Superfinish processing of the springs results in increased durability and spring life.Kit includes:#7230-16 Conical valve Springs#772-16 Titanium Retainers#623-16 Valve Locks#511-16 Valve Seals#4680-16 Spring Seats