COMP Cams Valve Lock 5/16in Single Groove

This product includes a pair of hardened steel street locks from COMP Cams. Each lock features a single groove and a 7-degree angle, designed to fit a 5/16-inch valve stem. These are intended as a direct replacement for stock engine rebuilds, particularly for street applications where valve spring loads are lighter.

It's important to ensure your valve locks match your valve size precisely. When properly installed, there should be a small gap between the two halves of the lock. If the halves meet without a gap, they are too large, and if they fit tightly to the stem leaving a gap between the middle of the lock and the stem's outer diameter, they are too small. The tang on the valve lock's primary role is to temporarily position the lock, retainer, and spring until the retainer's taper seats around the lock, creating a secure collet effect that holds everything in place under spring pressure.