Originally Posted By: Ken2
Do you want to use the oil for engine lubrication or as a heat exchange medium? If for a heat exchanger, use thermal oil.
For engine protection, use any of the many very well formulated modern oils. In any case, oil needs to be normally warm, somewhere in the 200°F range. If you need more cooling, especially in your Arizona region, get an oil cooler including a thermo-bypass valve so the oil does get normally warm before it is directed through the cooler. You may also consider increasing the oil's viscosity one viscosity grade higher than your owner's manual recommends or using a synthetic oil that thins less when very hot and has greater resistance to oxidation.
its motor oil, for a car motor.
engine oil serves 3 major functions:
1. lubrication
2. cooling
3. moving dirt to the filter
now, in hot places (many places in southwest US) during summer months its not always required to have a multigrade oil, and one of the perks of straight oil is that is is suppose to cool better because of less additives. thats what i know about it and i dont have time or test gear in my lab to do scientific testing.
the article i had read also talked about why pure water in the radiator cools better than a anti-freeze solution (but pure h2o is not practical, so a 80/20 water:anti-freeze mix is suggested, etc).
i lost where this article was, so now i have to go digging. this is more scientific (chemical compounds, specific heats, etc, etc). i just need to clarify what i had read.... i believe it comes down to specific heat of the oils in question, but i cant find specific heat charts for various oils and oil grades, etc.
