You just need to get a quality gauge.

Dakota Digital makes one that reads accurate compared to the VDO's.
If you want to know why, search the archives or thesamba.com, theres a
ton of info about em.

I havent seen mine climb above 400 yet, but no trips uphill yet.

Raymond Paquette wrote:
> I've had both head and oil temp guages on earlier ('66 and '71) busses, and
> don't think the head temp was very useful.  Once warmed up, it only climbed
> above 350 if I did things I shouldn't, like push up a hill that was really
> too steep for the gear I was in.  While you can cook your heads pretty
> quickly, it should really only happen if you're messing up.  Interestingly,
> it did give me info on tuning, like it would settle around 335 when I
> had my
> points and timing set right, good spark plug wires, good gas.  If it
> hovered
> higher (without obvious cause) I knew I had some maintenance to do.
> Outside
> air temp made little difference, aside form how long it took to get warmed
> up.
>
> Oil temp can climb without you realizing it though.
>
> I've had external coolers as well.  Best one had an electric fan that
> turned
> on  around 170 degrees.  You can also get an oil thermostat to keep from
> overcooling.  It bypasses the cooler until you get up to temp.
>
> If I had to choose one thing to keep me safe, I'd go with the oil temp
> guage.  You can always slow down and/or downshift to keep them temp down.
> My guage saved my ass several times when the oil bypass plunger stuck down
> (bypassing the stock oil cooler).  Without it, I wouldn't have known until
> something really bad happened.
>
> My $.02

>