There has been some talk recently about air-cooled engines running
cooler with some oils than with others. So I asked Ed Hackett for his
opinion; he is the author of a motoroil FAQ that has been widely
distributed over the internet. I'm forwarding this with his
permission.  

-Sami ('75 Westf.)

---------- Forwarded message ----------
Date: Mon, 28 Oct 1996 18:20:01 -0800 (PST)
>From: Ed Hackett <edh@maxey.dri.edu>
To: Sami Dakhlia <dakhlia@wuecona.wustl.edu>
Subject: Re: motoroil and specific heat

Sorry to take so long getting back to you, but work is keeping me out of 
the office about three weeks a month.

I ddon't have any specific information on specific heat other than the 
synthetics perform much better as coolants.  This is due to two effects, 
both a better heat transfer capability and less heat produced in the  
first place, due to lower internal friction.

I've seen the oil temp drop a bit more than 30 degrees F in a Bug  by 
switching form GTX to Valvoline Synthetic.

Any of the full syntetics should help lower the oil temp.  Mobil 1 15w-50 
is a good value, and easy to find.

 Ed Hackett   edh@maxey.dri.edu           The Desert Research Institute 
 DoD #0200  WMTC  BMWRA  DIOC             Reno, Nevada   (702) 673-7380   
 KotLS  KotLE  DotD #0003            I'm not really a chemist, I'm just one of
 BMW K100RS, Moto Morini Camel       them motorsickle sonsabitches.  __=o&o>__