Oil zddp ?

KnuckleDuster said
Anybody got specs for Valvoline VR1 Racing Oil 20w-50 handy? (silver bottle)
Been running Mobil Delvac 15w-40 with no issues but thinking of switching. Think it's worth the extra coin?

I have one Duster on VR-1 10w-30. First time using it. Because of other things going on with the car, it's hardly been driven. But, the break in went well and so far so good.

DrCharles said
A "good oil" presumably containing over 1000 ppm and preferably 1200+ of zinc?
That's the whole point of numerous discussions, every year the ZDDP gets reduced in various brands of oil... big spring pressure could be trouble even if you have a name brand with less than 800 ppm...

Spring pressure needs to be kept in mind for sure. I never over-kill the spring pressure. But, I really don't ever go past 6000 rpm's...... Although years ago I had a 340 that seen 7k a few times.