The Magnum head assemblies come equipped with one-piece stainless steel valves, each with a single groove for locks, and steel retainers with 7-degree locks specific to the Magnum. Valve sizes are 1.92-inch intake and 1.625-inch exhaust. This is quite an improvement over the 1.88/1.60-inch valves in earlier 360s. The valve stem is significantly reduced in diameter to 8 mm (or about .315 inch) as opposed to the older LA engine's 31/48-inch stem, which is .375 inch. This is a significant weight reduction at the valves. The single spring with a wound damper is similar to the early HP spring and more than ample for high performance street duty.