Oil Pressure and RPM Drop

Over the weekend while driving my car every time I would come to a stop, the oil pressure would drop to 25psi and my rpm would drop down to 500-600 or so. This has never happened before and my car has always run at 50psi and 900 rpm while idling. What is causing this, and is there problem somewhere?
 
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Your idle at 600 is a tad low, but 25psi oil pressure is just fine. Mine starts at 60psi then it warms up and comes down to 30. Sounds to me like your car is just warming up which causes the settings to change. You need to tune the carb with the engine warm, you may have tuned it while it was cold.
 
You are getting 30psi at idle (7-800rpm) when the motor is warm and with a standard pump? What's your secret? lol I can't imagine getting 50psi at idle when warm, that can't be good on the bearings.
 
I guess my concern was that whether it was warm or cold it always ran at 50psi, but know all of a sudden it drops to 25psi once I come to a stop. So it sounds like this is a normal occurence for everyone else. I guess I will just retune the carb to bring the idle up.
 
Believe it or not, the change in oil pressure from 500rpm to 900rpm could be close to 20-30psi. My car idles around 750-800 and i get around 20psi warm. Whenever i pull up to a stoplight (applying brakes), my rpms drop to 5-600rpm and my oil pressure drops to about 12psi. When stopped the idle goes back up to normal and so does the oil pressure. Cruising at 1200-1600psi i get around 40-45psi.

Is your motor still pretty fresh or does it have alot of miles? Fresh motors will naturally have higher oil pressure until it gets broke in, and then the pressure readings will drop (and continue to drop as the motor wears). Hope this helps a bit. I have a mechanical oil pressure gauge so readings are easy for me ;)