Varied Lifter Bore Oil Holes

Well, my thoughts continue to be that it is not really an issue. The hydraulic lifters should only take a little oil once they are pumped up, so if the oiling band on the side of the lifter is exposed to the hole into the gallery when on the heel of the cam lobe, then that ought to do it. The oiling band is not exposed to the gallery pressure when at any significant lift height; it just gets oil when down at the bottom.

And the good fortune in this situation is that the larger holes are on the lower pressure (driver's) side gallery. So at this point, we'll proceed as is.

But as said, if anyone knows of an issue associated with this irregularity, I'd sure like to hear it. I couldn't see anything specific on the 'oiling mods' threads on this, and the 'tube and peen' mod is not meant for hydraulic lifters, though I suppose one could make it work.