These hardened steel, single groove Steel Street Locks with 7? lock angle and 3/8" valve stem size are perfect replacement locks for stock engine rebuilds. They are recommended only for street applications with lighter valve spring loads. It is critically important to make sure valve locks match the valve size. There should always be a small gap between the two halves of the lock when they are properly positioned on the valve stem. If the two halves fit together without a gap, they are too large. If the locks fit tight to the stem and leave a gap between the middle of the lock and the O.D. of the stem, the locks are too small.
