800 open pressure on flat tappet cam WTF.......no wonder there were lots of wiped out cams.I was around the Winston Cup series in the mid 90's the first time they pulled the stunt Leefus mentioned. Flat tappet cams with 800# open pressure back then. LOTS of cams wiped out. Yes, Rotella has it's fans, and there are plenty of success stories. A few years ago I did some research into base stocks and additive packages in oils. Partly for work and partly for my own knowledge. I went with Amsoil. They have special break-in oil, oil with higher ZDDP content for the flat tappet stuff, full synthetic for my newer vehicles, stuff for my tractor, etc. No, I'm not a dealer.
Just a couple thoughts, as in the big picture most any oil will do for long-term wear. That said, break-in with potential for scuffing is a concern that today's engines do not face, with advanced machining and materials control.Stock rebuild with .030 over bore. 4bbl carb.
A little confused about break in oil after reading so many different replies.
Rotella 15-40 with additive for the first 500 miles?
Just regular 30wt and additive?
What ye say?