Need some help - loosing oil pressure at high rpm's

[madmaxx]

Hey guys I am no engine expert but am pretty good. 351 stroked to 427. By the gauge on the dash my oil pressure is 35 -52 psig from idle to 4K. Once it hits 4K oil pressure drops rapidly to 45 psig and stays there through 6K.

Here the kicker I checked oil pressure before the oil cooler and it pegged at 65-69 psig all the way to 6k rpm's. no drop what so ever. is the oil cooler or oil pump the problem.

Additional details:
Mellon high volume oil pump
8 quart pan - I dropped and calibrated dip stick originally of 1.5 quarts!
Superformance Cobra with recently replaced oil cooler by previous owner why I don't know as he is NOT A CAR GUY nor are his mechanics
I checked rod and main caps they were immaculate as was the rest of the internals of the engine. zero particles in the pan. I couldn't believe how great it looks inside there. cam, dist gear all perfet. Checked compression and all were 195 -200. I took apart the oil pump it looked perfect I did crank in on the rv screw a little which appeared it did help. as before it was dropping from 50-40 psig.


how do I work around this problem? when cold the oil pressure was 70 psig and the rv lifted. is there a limit on the oil pump pressure I want to avoid?

Thanks!!!!!!