E30 M3 - oil pressure

I finally got round to hooking up my oil pressure
gauge, the gauge has been there but not wired up.

I'm getting:
7bar - stone cold
4bar - warm idle
6bar - > 2500rpm or so.

Found this in a past post:

Idle                  &nb sp;  0.5-2.0 bar     (7-28 psi)
Top Speed       4.0-6.0 bar     (57-85 psi)
The "Top Speed" is NOT the engine top speed, but
rather any speed above the
point where the pressure relief opens.

Question is why could mine be showing so high?

OR - is this correct what are the BMW book specs?

Is it possible to wire it up 'wrong'?
I have a CA automotive electrical gauge. 10bar
sender with a t-piece. There are 3 connections, 1 to
the gauge, 1 to chassis, 1 to switched 12v supply.

Could the switched 12v supply be affecting this??

Hi Uwe, I didn't remote fit it, I got a mocal t-piece. It
has a M12x1.5 male thread a M12x1.5 female thread
and a 1/8 npt female thread for the sender unit. Yes
the sender unit did come from the same people who
make the gauge.

It didn't 'fit' first try as the sender take off was not
aligned, i just used 2 crush washers instead of 1 as
it tightened up it aligned perfectly with the space
behind the alternator, (it points straight out at you if
you looked at it, I'll get a pic) I just had to re adjust the
dipstick bracket a bit for the low pressure switch to fit
properly.





Edited by 215DMX

Just thinking, I use Porsche 928 oil filters - though I
wouldn't have thought it would make any difference.