I don't mean to beat a dead horse, but this question keeps coming up. How much zinc is necessary for a Y-block that has been properly broken in? I seem to recall Ted saying that he uses Valvoline 10w40 Conventional Daily Protection, which, according to Valvoline, has 760 ppm. Others seem to think the oil should contain 1200 ppm. I don't see how you can prove with 100% certainty that you wiped the cam because your oil didn't contain enough zinc.