Oil pressure will drop as the engine warms up. I run 12 to 15 psi at idle with the engine at operating temp. with 20W50 Castrol GTX oil in it. It will run 65 psi when it fires up and 45 psi at 2600 rpm going down the road. These readings are off a mechanical oil psi gauge. I would be skeptical about trusting the stock gauges a whole lot.