Oil has an operating temp range. Max temp depends on the
oil. The chemical engineers that made it can tell you what it that is, but they won't. Generally speaking, dino
oil should be below 240*, and
synthetic below 300*. Those are general guidelines, and diffferant formulations will vary.
Engine bearings will start to increase wear when the bearing temp is greater than about 250*. Bearing temps tend to be about 70* hotter than oil temps. You can do the math on that one.
Oil DOES NOT have to be above 200* to evaporate collected moisture. If that were true, your kitchen floor would never be dry. It just takes longer at a lower temp, just like your floor.
Minimum temp is generally accepted to be about 180*. Engine ring wear will increase to about 0.001" per thousand miles when oil temps are below 170*.
An oil thermostat is a must on a street car; just like a water thermostat. The oil thermostat should always pass some oil through the cooler to allow all the oil to warm up evenly. Unfortunatly, on a street car that can mean the oil never warms up to operating temps. On cold days, put some tape over the cooler.
For a street/track car, the optimal set up would be an oil-water heat exchanger. That will keep the oil and water temps about the same, regardless of temp. But that may put too much of a strain on the radiator, having to shed heat from both the water and the oil.
Hybrid Mode
