I just thought i would post this as It was included with my Lazer cam recommendation reply.
Under pressure from the major Detroit automakers, the engine oil manufacturers have removed the zinc additive from engine oil. The really bad news is that this increases camshaft and follower failure rates enormously during, and after the break-in time. If you can find a zinc additive for engine oil, that helps greatly. GM's EOS break-in lube has been a faithful option, too. I understand that Valvoline and Kendall racing oils that are labeled "not for highway use" still have the zinc in them.
There have been no changes in camshaft or follower materials or heat treatment from ANY of us in the racing aftermarket. The increased failure rates are due to the missing zinc in addition to the usual assembly related problems we've been discussing the last thirty years or so. Keeping open spring pressures as low as possible is now more important than ever.
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