I have a digital oil pressure gauge with the transducer mounted in the rear of the drivers side head up against the firewall. I am using Mobil 1 5W30 oil.

On startup it usually runs between 40-70 psi but under normal conditions, when warmed up, at a stop sign it will usually drop to between 20-25 psi. On a few occasions while towing and idling it would drop to 19 or 18 psi. However it generally drops to the lower 20's.

These are readings I have always been getting since I installed the gauges 4 years ago.

Is this an acceptable pressure at this location?

 

I also have a digital gauge. Use Mobil 1 5-30. Startup it shows 71. After it warms up it shows 61 at 70mph. Idling at light it shows 24.

 

As hot as my V10 has gotten, it's gotten at low at 24PSI - that's from the port where the stock oil gauge sender is in.