Do the two closely follow each other?
If running a 180°F T'stat, will the engine oil temp similarly be 180°F, like the water temp?
Are there situations where the two will vary?
Would an engine oil temp gauge be beneficial over water temp?

 

Oil temp is going to be hotter. After all, it doesn't go thru a cooler. The pan acts as the cooler. It works, after a fashion.... for hard working engines, and external cooler really isn't a bad plan. You want a thermostatically controlled unit though, as over-cooling is just as bad as over-heating.

 

But should the two follow each other with any predictability?
We know the standard temp gauge isn't very accurate... could oil temp be monitored to the same end, in lieu of having a duplicate water temp gauge?

I'm in FL, and was planning on an engine oil cooler at some point, not that I have temp problems, but just to help even out thermal load on the engine.

 

^yes, sort of. the oil is pumping/splashing/draining its way around the block and heads. the antifreeze is also circulating around in the block and heads and its temp is measured at its exit at the tstat neck. so, with everything working correctly, the oil in an engine running at coolant temp 180 will be something (180x) and the oil in an engine running at coolant temp 240 will be something else (240x). what those exact temps are- i don't know.

you can probably get a simple plumbing kit that fits onto the oil filter post that will have the fittings, hoses, etc to run an cooler, fit in a gauge, possibly move the filter, etc.

 

There are remote filter and cooler adapters available at a reasonable price.
Something for me to work on later.

Thanks for your input.