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

[madmaxx]

Update: I bypassed the oil cooler. I had 66 psig at cold a big jump from from the 58 psig when cold before. In the end once the oil came to temperature it was back to 50 psig and would pull back to 46 psig above 4k rpm, which was better than the 43 psig. The 10AN lines and fitting result in less than 2 psig drop. The oil cooler pressure drop matched the one I had on my last cobra at 7 psig. So in the end the oil cooler is not the issue although I do not recommend them.

1) Oil pump, oil pump pick-up pan, baffles not an issue
2) Oil cooler and associated lines not an issue

I did pull the original dyno sheet and this engine from had 57.8 psig oil pressure at 6krpm. My last one had 70 psig. Who knows if the builders gauges were accurate.

I doubt it is the bearings. The condition of the engine is perfect, compression test checked great, no oil consumpiton, no contaminats found in pan and it is quite as compared to my last one which sounded like a box of marbles. In the end it might just be characteristic for this engine. Time to drive and enjoy!!