Well, since I built the shortblock, I should chime in..... you guys out there feel free to comment on my comments....
OK, with 55 or 60 psi cold idle there are no missing plugs. If you have them available, go back and look at your dyno sheets to see what the pressure was during the runs. The motor should not have lost very much pressure since its first start. It will loose a tiny bit, due to break-in but not much. If you look at your pressures, they are about 10 to 15 pounds less than what everybody says is "normal", which is what you would gain by adding the restrictors. The Edelbrock heads are worse about bleeding
oil pressure than stock heads were - they have a real big passage up to the rockers.
As for the extra 1/2 quart of
oil, I wouldn't bother with that. It won't make any difference. The cooler will most likely drop you down another 3 or 4 psi, so you really should look into getting the restrictors installed.
You can do it without removing the heads if you use dowels. You will have to take off the rockers and measure the hole where the
oil comes up from the head into the rocker stand. I think I remember you said you bought a micrometer, or maybe it was a dial indicator - anyway, use a good method to measure it because you want the dowel to fit tight but not so tight you have to use a shop hammer to drive it in. Have a local machine shop turn down 2 aluminum dowels that are your measured diameter by about 3/4" long. Then have them drill a .080" diameter hole right down the middle of it. Bring them home and insert them into the holes and re-install the rockers and valve covers. Problem should be solved.
One thing about your engine - since it has LeMans rods, the rod side clearance is high. They are old rods, been around the crank a few times, therefore the side clearance is not as tight as it used to be. Don't get me wrong, they are good rods - yours were re-sized, re-bushed, beamed, peened, polished, new bolts, new dowels.... they are not going to cause you any problems other than the inherent loose side clearances. I would install the restrictors, use straight 30wt or 40wt oil and drive it. Just for kicks, you could get it warmed up, take the distributor out and one or both valve covers off, and spin the pump with a drill. I think you will be shocked at how much oil is being pumped up there. Be careful though, you can make a mess real quick by overflowing the heads and coating your headers - and smoking up the neighborhood next time you fire it!
Thank you and have a blessed day!
Randy Ritchey, P.E.
1834 W. Arrowhead St.
Fayetteville, AR 72701
479-527-9166 office
479-841-7142 mobile
rritchey@cox-internet.com