Drilling oil galleries and oil return holes?

yellow rose said

9/32 (.~.287) is big enough. I don't drill the feed any bigger to the drivers side lifters. They get more then they need.

Click to expand...

If the lifter bores were worn, then it would be a good idea to do so. And use the HV pump with all of this IMHO. The lifter bore wear is all over the map on these engines anymore.

I agree on the drill size. But I went to 10/32" (5/16"). I drilled carefully with that bigger size!