Got a muscle car w/ a flat-tappet cam having any significant open spring pressure at all (over 250#s)?
- Amsoil Z-Rod (only available in synthetic)
- Driven Hot Rod (available in conventional or synthetic)

Don't Band-Aid other oils w/ pour-in zinc additives 'cuz there's no guaranty the two products will mix successfully.

Buy good stuff designed for the proper application. Today's generic passenger car oils are NOT.

People ask the question, this is my OPINION... not up for debate... follow my advice or don't. Your car, your cash.