[panhead59]

I've got some ZDDPlus from a local auto parts store. They all sell it. It says that it will "restore ZDDP specs to SF levels". It also says it will only "treat" 4-5 quarts, and most of our engines hold 6 qts. or more. So is there enough zinc in the SF level to protect our flat tappet cam/lifters? The Valvoline oil I have is rated at SN/SM, ilsac gf-5. So that exceeds the SF level with the SN/SM oil. Or does it? (as far as the zinc goes?)
Don't mean to start this very long and contentious debate all over again, I just can't find a good, high level zinc oil locally. The best one I've found around here is Valvoline racing oil and it's 50 wt. I realize that I can always order it somewhere and get whatever I want. What do you think?