While I agree that new oils are fine for older engines that are already broken in, it is preferable to have a hight level of ZDP (zinc) in the oil during the crucial break-in phase of a new camshaft and lifters. Sometimes, new oil standards works fine, sometimes it doesn't...I witnessed new cam failure on a fresh rebuild a couple years ago. We primed the oil pump, started up the engine and went straight to a fast idle intending to keep it there for about 20 minutes. About 10 minutes into the run, the engine died and lost compression on all cylinders. Culprit was a failed camshaft. Not positive what caused it, but from now on I will make sure that the break-in oil has ZDP in it.
