I believe its supposed to be below 30psi at idle when already warm. I believe mine is below 20, its normal.

 

<-- noob

 

Lol Werd.
There were a couple threads at the repairing forum regarding the idle oil pressure at operating temp.
Mine is around 10psi after switching to Mobil 1 10w-40 from conventional oil.

 

I am also at 10PSI at idle with Mobil 1 10w-30.
You should be around 30-40psi when you are driving normally after your engine warms up. The oil pump is driven by the engine, with a gear pump, this positive displacement pump is totally dependent on RPM for Flow, thus the lower the RPM the lower the flow the lower the pressure for a given viscocity. When your engine is cold, the oil has a higher viscocity thus for the same flow rate you will have a much higher pressure. That is why they give your oil a range of viscocities (10w-30), one is for cold, the other is for warm.

Hope this helps.