Oil zddp ?

Well, if your going to pour the little 8 oz. container of ZDDP in the valve cover, then pour your oil in afterwards hoping the most of it washes down in the pan, it might be a good thing they sell it already premixed....

Where do you think the 8 oz. ZDDP could go, that 256 oz. of oil poured in the same opening won't get to it and carry it to the pan?