Lighter is faster.
One of the best ways to go faster is to make things lighter. Lightening parts in the valvetrain is one of the more effective ways to benefit from that principle. Decreasing valvetrain weight allows you to rev the engine higher and make more power--reliably. Crane titanium valve spring retainers are designed with that in mind. They're machined from premium titanium-alloy bar stock to deliver the quality, durability, and reliability you expect. They're available with either 7 or 10 degree internal tapers to work with popular valve stem locks.
Valve Spring Retainers, Titanium, 7 Degree, 1.630 in. Outside Diameter, .635 in. Inside Diameter, Set of 16