I was in the Tech section where this question was posted, and I have the same question. In my '72 the oil pressure gauge always reads 3 bar. Even when fully warmed up, at idle, in warm wheather (yes, I mean fully warmed-up).
I think the gauge functions correctly as there is a short delay before it climbs up when starting, and the delay is longer after an oil change.
The motor runs well, with no leaks, blow-by, or smoking, and the thermostat is working correctly. I just thought I'd throw this out there, TIA for your comments.

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