Hi Doug,

 

I wonder if your car's oil temperature sensor is measuring the hot oil leaving the engine.  I'm pretty sure that my IO-550's oil temp sensor is measuring oil temperature of the oil leaving the oil cooler, before cycling back through the engine.  That could account for a large difference in measured oil temperature and in acceptable oil temperature limits.

 

Also, automotive motor oils have different additives than aviation motor oils, which might also account for different oil temperature limits. 

 

Interesting question!

 

Dennis Johnson

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