Oil Pressure 3.2

My UK spec 88 Carerra runs at around 4.2 bar (on the 0 to 5 bar gauge). I've read elsewhere that it should be 7 bar (off the gauge??). At idle, it drops back to 2.5 bar. I guess these figures represent 59psi and 35psi. Does this seem about right or is it running a touch low. My mechanic reckons not to worry as the gauge accuracy can vary wildly from car to car. Any opinions?

Factory oil pressure spec's. are approx. 4.0 bar @ 5000 rpm at 90 degrees C. As long as your oil lamp does not come on at idle when hot, there should not be a problem.

Thanks Lee. No, the oil pressure light stays firmly extinguished at idle. Seems my pressure is pretty close to where it should be. Thanks for the reply....I appreciate it.