ok guys, 1st, thank you for all your replies and input. I will try to answer all your questions best as possible. The engine is original 70,000 mile motor, 390 Thunderbird engine, 390/300.
By standard rebuild, I meant all standard sizes, bores, rings, rods, mains, all standard sizing. Camshaft is a new Doug Herbert GN4 hydraulic, Doug Herbert lifters, matching Doug Herbert valve springs, melling high volume oil pump, new stock rocker arms and shafts, comp stock length pushrods.
The engine was assembled by myself and the block was prepped by my engine builder who is also Ford specialist, as were the heads.
I pulled the valve covers off, seems to be plenty of oil getting up top. problem seems to be with #4 & #8 intake valves, I'm going to try to sneak those lifters out without pulling off the intake manifold. I want to visual those lifters for damage on the bottom, also for any blockage in lifter valving. let you know if I find anything. But I'm inclined to think the push rods may have a lenght problem because of the new cam.