COMP Cams Valve Lock 3/8in Two Groove

When you're rebuilding the top end of your engine, getting the valve train components seated correctly is crucial. These COMP Cams 3/8 inch two-groove valve locks are designed to work with stock engine rebuilds, ensuring your valve retainers sit properly on the valve stems. They are made from hardened steel and feature a 7-degree angle, which is important for how the retainer nests around the lock.

It's important to understand that the tang on these locks is primarily for temporary positioning until the retainer's taper engages. The real holding power comes from the 'collet' effect created when the retainer seats around the lock, binding them together with spring force. These locks are recommended for street applications with lighter valve spring loads, and it's critical they match your valve stem size precisely. If the two halves fit together with no gap, they're too large; if they leave a gap between the middle of the lock and the stem's outer surface, they're too small.