Is zddp for the cam lobes during break in, if it is comp cams says it only needs to be used for 20 minutes. The additive does not need to be put back in after break in
I put the lucas stuff in with every oil change in order to get zddp levels up to what they used to be for performance oils. It is a very effective lubricant in preventing wear on grey iron surfaces (like lifter / cams) and increases antiscuff properties dramatically.