With the emergence of valve sizes other than 5/16", 11/32", and 3/8", it is important to make sure valve locks match 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 are in contact without a gap, the valve locks are for a bigger stem. If the locks fit tight to the stem and leave a gap between the middle of the lock and the stem's outer diameter, the locks are too small for the valves. All locks should be checked before final installation to ensure they're the correct size.
Comp Cams 7° Street Valve Locks are made from stamped, hardened steel. Designed for stock engine rebuilds and only recommended for street use with lighter spring loads. The 7° Race Valve Locks are available in Machined Steel or Titanium. They offer the same valve spring location accuracy as the 10° Super Locks, without the need to change to 10° retainers. Comp Cams 10° Super Locks handle higher spring pressures by distributing load over a larger area. This reduces the chance of a "pull-through" failure. Recommended for all race applications.