I agree with the low amount
Zinc & Phosof in todays
oil. Using break in lube for a new engine is essential,...... especially with flat tappet cams.
I go ahead and use this
oil all the time, not just for break in.
The most important issue, CHANGE THE
OIL OFTEN ,.... not just every 3,500 miles like you daily driver. If I drove mine hard, I change it, as well as when I'm driving in dusty conditions, especially with my oval cobra air cleaner sucking up the dirt directly in the hood scoop. Or when I've been on the chassis dyno.
I also agree Excaliber, using a supplement such as Lucas, STP, ext. If you don't over use these products, I don't see how it can hurt. Do they help, ???
All I know is, I haven't had any issue's with my flat tappet.