I read a past thread from last year about comp cams. There were many intelligent and experienced people guiding us through the situation at hand. I would like to add that with today's oils, damages could occur. Not to back any manufacturer but the oils of today either contain no zinc or very minute. All metals are porous and the zinc voided softness and weak spots throughout the whole engine. Now that oil doesnt contain zinc due to expense all manufacturers and suppliers are leaving iron parts alone and continuing with steel and aluminum. For most circumstances as long as you utilize zinc additive along with oil or pay the extreme high price for oils including sufficient amounts of zinc, problems for the most part will be null. Also to add just because you use zinc doesn't mean parts will last forever it'll just prolong life.