I honestly think most of it was caused by the wheel. I never primed one like this and was shocked to see the wasted oil shooting out as my son ran the drill priming the engine as I slowly turned it over with a breaker bar. I wish I had video of it to post.
So oil out the top of the bores, or out the bottom past the wheel? Out of the tops would seem to be a matter of bore clearance ....???
I was just looking at this: http://www.hughesengines.com/Upload/BAM_lifters/BAM.pdf
and see that the 2 designs have different oil restrictions to the roller area. Not sure if this would make any big change in the flow out past the roller.