Originally Posted By: Shannow
That's the onset of hydrodynamic lubrication where the surface additive layer isn't part of the deal...surfaces have "lifted off" so to speak.
Just ran out to the shed, and measured the lobes on a BMW M20 camshaft I've got lying around...lobe"circumference was 10cm...at 6,000RPM, the average surface velocity is 6m/s...at highway speed, it's only 2m/s.
So, Youre cruising ar 2k rpms, and the ZDDP layers are touching and churning each other, creating a little drag. That doesnt happen at large contact areas as bearings and liners, where Thick Film Hydrodynamic occurs, cumulated with higher speeds, right?
So, a lttle clorinated paraffin in EP could plow and smooth those layers...