Quote:

it has a solid roller cam with .760, .716 lift with 1.7 T&D shaft rockers. Maybe the lifters are uncovering the oil feed?

It could be the lifters/bore, but I don't think so. That is not a lot of lobe lift:

.760"/1.7 = 0.447"

So a normal 1.5 rocker arm (stock head) would only be 0.670" valve lift with that cam. And tons of guys have run that in stock blocks, rocker ratio, etc. And on top of that, the roller lifters from IMM should not be a problem at that lobe lift either.