Lots of opinions on this. I use VR-1 in my flat tappet cam motors and have never used ZDDP additives.
I initially used Mobil One. But a couple years ago I read some articles that stated it had been reformulated and no longer was adequate for flat tappet cam motors.
Thing is, when you buy oil, you have to be diligent and read the bottle every time you buy it. They change the formulas but don't waive a flag in your face when they do so.
I've also heard that if you are running a stock cam and stock valve train the pressure loading on the cam lobes is so low that once the the motor is broken in you can run any oil you like and it will be just fine.
For me, the VR-1 works so I'll stick with it.
Hope that helps
John
