Antiwear compound content such as ZDDP is generally talked about in terms of a proportion of the total mass of oil. ie 1400ppm or 0.011% etc.
Because of the mechanism of protection, isn't the most important thing being the total quantity of ZDDP in the sump of the engine that is available to form the protective film under heat and pressure?
To illustrate this question more, assume I have two identical engines except that one has twice the oil capacity to the other. If the large sumped engine contains 10 litres of 700ppm ZDDP oil and the other contains 5 litres of 1400ppm ZDDP oil, if all else is equal, won't the protection afforded by the ZDDP be the same in both engines?
Thanks
Peter
Because of the mechanism of protection, isn't the most important thing being the total quantity of ZDDP in the sump of the engine that is available to form the protective film under heat and pressure?
To illustrate this question more, assume I have two identical engines except that one has twice the oil capacity to the other. If the large sumped engine contains 10 litres of 700ppm ZDDP oil and the other contains 5 litres of 1400ppm ZDDP oil, if all else is equal, won't the protection afforded by the ZDDP be the same in both engines?
Thanks
Peter