Oil pressure can vary a lot in normal operation, high on take off, low at idle when hot, but generally in the cruise, after all t's and p's have stabilised, it will be very consistent. If not it's cause for concern.
"I like your investigations. Everything you have said is true. This is why I take my engine overhauls very seriously. LOW OIL PRESSURE CAUSES MUST OF THE PROBLEMS, DUE TO WARE AND TEAR of the connecting Rods. This microscopic metal fatigue could be prevented with constant lubrication after every two flights or? Every 30 minutes of engine use(This means? Check your engine after every thirty minutes of flight, even if it appears to run properly. This also means? Keep four extra quarts of aero shell oil, or a oil of your choosing on board; To keep oil pan bay at it's max for an easy and lube flight, where ever you may travel as an operator. Remember? The oil spits out this engine constantly at high pressure. Therefore? You must check the engine at a constant to maintain a level and plausible flight with every takeoff no matter the weather condition.) check engine.
