Classic/Antique Car Repair: Packard low oil pressure?, Oil pressure worries

Question
Hello Dick - The oil pressure gauge on my 1949 Packard Super Eight registers 15-20 at idle with the engine warmed up. From what I have read, this is lower than normal. Is this something I should be concerned about? I have owned the car for 5 years and the only engine work that I know of was a valve job aprox. 8 years ago. I use 30W oil and drive aprox 2000 miles/year, never over 55 mph. It is a very nice car, has been well taken care of and drives well. There is no exhaust smoke, engine is quiet with good power and acceleration. "Puddles" on driveway are minimal and there is no engine knock. When driving at 50 mph, pressure registers 25 or so on gauge, never above 30. Just curious about the significance of this oil pressure reading and if it indicates an impending major engine overhaul. Thanks for your help.
Charlie Cain

Answer
That oil pressure is fine, you have no reason to worry about it.   Starting a few years later, the gauge was eliminated entirely, for a so called "idiot light" - for which the threshold was 7 PSI.  Further, the manuals in later cars said not to be concerned if the oil light "flickers" at idle with a warm engine, meaning that the oil pressure dropped below 7 PSI at idle.  This was for the same engine design as your car.

The threshold for serious problems is when the hydraulic lifters begin to clack - this is about 6 PSI at the lifters.  This is not to make you worry when you hear an occasional tapping from one lifter - if there is a serious oil pressure problem with the engine, all 16 of the lifters will be clacking loudly at idle - that is the real tipping point to deal with a low oil pressure situation.

Just drive your beautiful car and enjoy it without worry.  I have a '47 that I have been driving since 1967 - I rebuilt the engine at 141,000 miles, and have since driven it another 138,000 miles, and other than one valve job at 210K, have never worried about it at all - these cars were really built to run almost forever, if given normal care.  My car gets driven at freeway speeds - 70+ for hours at a time (it has overdrive), and I hear no complaints from the engine.

Dick