The proper blue sensor is .25 (3.53 psi). I have the VDO 150 psi gauge with the 2 pole sensor which turns the light on at  .8 bar (11.1 psi). With my oil cooler set up I rarely have an issue with the light. 
Do you really want to not get a warning anyway with only 3.5 psi of oil pressure? This why the later vans got the dynamic oil pressure warning system. 

Dennis

-----Original Message-----
From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com] On Behalf Of Rocket J Squirrel
Sent: Friday, April 08, 2011 7:20 PM
To: vanagon@GERRY.VANAGON.COM
Subject: Re: I guess if I'm putting on a tencentlife oil cooler . . .

I'm confused. Is 0.3 bar lower or higher than the trip point for the stock sender?

On Fri, 2011-04-08 at 19:09 -0400, Dennis Haynes wrote:

> I prefer the two pole sensor. Turns light on earlier and makes for one less failure point.
>
> Dennis
>
> -----Original Message-----
> From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com] On 
> Behalf Of Chris S
> Sent: Friday, April 08, 2011 6:43 PM
> To: vanagon@GERRY.VANAGON.COM
> Subject: Re: I guess if I'm putting on a tencentlife oil cooler . . .
>
> Beware the two-pole sender. The oil light side has a low pressure 
> trigger that is a bit higher than .3 bar. Run a splitter and use a 
> factory sender for your light.
>
> Chris.
>
> Wysłane z iPhone'a
>
> Dnia Apr 8, 2011 o godz. 17:05 Don Hanson <dhanson928@GMAIL.COM>
> napisał(a):
>
> >    VW vendors sell a VDO gauge for pressure that has a small can 
> > like sender with two electrical 'poles'...one for your existing 
> > system...the warning light..and one to run the aftermarket gauge.
> >
> >  I don't know about the Waterboxer motor but on my inline VW motor I 
> > put it onto the sender down at the oil filter flange and it works 
> > fine.
> > You will
> > have to run a wire from back to front and what I did was use some 4- 
> > strand trailer wiring wire...I used one strand to get the pressure 
> > sender signal, one for my Oil temp sender and I have two left over 
> > for any other uses that come later on.
> >
> >  Don Hanson
> >
> > On Fri, Apr 8, 2011 at 1:21 PM, courtney hook <courtneyhook@shaw.ca>
> > wrote:
> >
> >> Mr Squirrel,
> >> Do yourself a favor and buy a good quality one that is electric, 
> >> NOT mechanical. What a nightmare running the capillary tubing for 
> >> mechanical gauges, not to mention the lag time. I used to run a 
> >> digital oil pressure gauge in my HP 2276cc Bug, which was very 
> >> accurate and looked good too.
> >> Nowadays you can get them from just about any big gauge manuf. Just 
> >> remember that the big ticket with these is consistency between 
> >> readings.
> >> It's good to
> >> know what the gauge reads as an average of what you expect to be 
> >> normal; not necessarily within 2 lbs. of actual pressure. If it 
> >> varies markedly from what you expect to usually see, THEN you know 
> >> something is up. Mine used to blink like crazy if the pressure 
> >> dropped below 20psi.
> >> Courtney
> >>
> >>
> >> ----- Original Message -----
> >> From: Rocket J Squirrel <camping.elliott@GMAIL.COM>
> >> Date: Friday, April 8, 2011 1:09 pm
> >> Subject: I guess if I'm putting on a tencentlife oil cooler . . .
> >> To: vanagon@GERRY.VANAGON.COM
> >>
> >>> ...I might as well look into rigging an oil pressure gauge.
> >>> Anyone got a
> >>> handy kit or anything?
> >>