Re: low oil pressure?
Do what I did,
Screw in a mechanical oil gauge so you can really see your PSI at idle.
If you can get one with a longer than normal extension, it'd be an idea to do a lap of your street to see the pressure under load.
This is how I diagnosed my cactus oil pump
Never trust your Factory Oil Pressure gauge. There are different VDO sender units for the Ford which also show different readings.
Low oil pressure is not good for prolonged periods and there are various problems that can and will arise..............but you need to verify the actual reading first.
@40 psi on HOT idle is OK and @60 - 65 psi when under load HOT
When Cold, it may get @65 - 70 Psi on idle
You will also find that your actual idle will vary the reading you are getting.
Mine idles at @780 RPM and my Hot idle is @40 PSI. If I Hold the idle to 800 - 850 RPM the oil pressure jumps to @50 PSI.
And you need to take your clearances into consideration and your Oil pump. Is a standard volume pump or Hi Volume ????? as this can affect your PSI slightly.