I have an OHC 6 that was a new short block installed about ten years ago. Since it was done when my uncle had the car, I'm not sure who did the work but I believe it was a dealer installation, since it was new. My uncle since has only put 3000 miles on the car. I inherited it, God bless his heart!, and I drove it home, 1200 miles or so. I didn't spend much time on the road before I saw, on a manual oil pressure gage, the fluctuation of the pressure when I turned hard one way or hit a dip in the road it would do it also. When I turned the other way, it would hold a steady 50psi. Wierd.... I stopped and had the oil changed in hopes of remedy of my problem. Of course the folks @ the establishment had never seen one of these engines and thought 4 and 1/2 qts would do it and I got the book out and showed them at least 6 qts. We did that and of down the road I went. I had checked the oil and was right up on the stick and figured all was good. Same problem... I nursed it home and figured on pulling the pan, loose pickup? Got the pan off; beautiful clean crank, bottom side of the pistons were like new. No loose pickup. What now? The baffle is in place, the pickup doesn't appear to be molested. Any ideas?

31 PSI +/- 5 PSI is the factory spec on the Oil pressure. At 50 PSI, you're grinding the followers into the cam. Usually that results in cam failure within just a few hundred miles.

It sounds as if a lot of oil is staying in the top end of the block, meaning that the cam is getting plenty of oil - but possibly a little too much for the stock valve seals.

Check the pressure regulator spring and slug in the accessory drive to be sure they aren't sticking.

Thanks! That would help explain why the problem is worse at highway speeds

My pressure is also varying a bit at highway speed-2800-3000 rpm(new rebuild-maybe 1000 miles)...new everything. Needle is at about 60 psi, then dips to 35/40, then back again. I guess the pan is momentarilly running dry...?

Should I be concerned?

Hmmm... With respect to Quenton's info, it could be going dry or if the pressure relief is actually sticking and oil pressure drops to 35psi and back up again, 35psi is what it is supposed to run. Maybe addressing the 35psi is going to be my first course because these engines have a lot of cam difficulties anyway and don't need to be driving the followers into the cam. Anybody else got suggestions?

Did you ever see the move "Wedding Crashers?"

Maybe, not sure.

Ever see Taxi Driver?

It could also be the gauge if it fluctuates with road conditions.