comp cams valve spring shim, steel, hardened, 1.640 in. od, .635 in. id .030 in. thick, set of 16

As with all other parts in the valvetrain, the area where the spring sits takes a beating. The old standard shims simply will not hold up to the extreme pressures and high rpm found in today's performance engines. COMP Cams offers this set of valve spring shims to solve this problem and eliminate failures.