[1971455HO]

It may be nothing, but I wanted to ask. Its been 2500 miles since rebuild. Using Castrol 10W30 w/comp cam break-in (cam lobe protection) dumped @ 500 miles. Replaced with same oil & additive. Got 2000 miles on this oil change. Planned on changing it @ 3000.

Original nodular 3.25" HO crank with standard rod & main journals. Clearances are .0015" rods & .0015" mains, with .009" end play checked at thrust and x2 side rod clearance is .015". I went with the Melling M54DS 60 psi pump. I thought that was the right choice.

Cold (first start-up of the day) oil pressure is rock solid 65 psi. I keep it on fast idle @ 1500 rpm until a little heat (140*-150*) is in the motor before I rev it to get idle down to 700 rpm to back out of the garage. Oil pressure drops to 50 psi after the first 15-20 minutes of driving back roads @ 45-50 mph. Then I get on the freeway. Oil pressure drops to 45 psi after 20 minutes of sustained freeway 65-70 mph driving.
My concern is, lately I have noticed my oil pressure drops to 20 psi @ idle after getting off the freeway while waiting at the traffic light. Slowly goes back up with a pretty good rev of the engine while sitting still. Goes back up to about 35 psi @ 45 mph on secondary roads while at full operating temperature.

What do you think boys...good...OK...bad...OMG? It's a 60 psi pump, not the SD 80 psi pump. SD's were built a little looser. Mine will never see anything above 5500 rpm.

I run 10W30 based on the crankshaft clearances. Didn't want to strain the cam/distributor gears running too thick of an oil. I do live in the South, it's hot down here, 95* at the Pontiac show this last weekend. I know viscosity goes down as temp goes up.Should I be using heavier oil fellas? Maybe 10W40...You boys in Texas ought to know 'bout right now.

one last stupid oil capacity question. I fill the filter full, screw it on and add 5 quarts of oil to the pan. I've adjusted my dip stick with a spacer to reflect that as full. Should it be 6 quarts in the pan instead of 5 quarts?

thanks,
Eddie