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Old 08-19-2015, 12:14 PM   #53
bluesubie
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Excellent post!

Quote:
Originally Posted by rice_classic View Post
So Cem is right, running around all day at 7000rpms is just fine at high rpms using a thin oil even at high heat. But can I also be right? Well, the answer really is: It Depends.

Hydrodynamic oil film thickness is directly proportional to the viscosity of the oil.
And I think this says it all.

Yes, you want to run an oil that is thin as possible but as thick as necessary for your application. What you don't want is sustained running in the Boundary Lubrication regime and this happens even in some daily driven engines.

http://www.bobistheoilguy.com/states-of-lubrication/

This is why some people are having very good results with street/racing oils like Red Line xW20 and Motul 300V 0W20. It is a thin oil when hot, but is loaded with anti-wear additives. In boundary lubrication, you're 100% relying on the additives because the oil film may have permanently or temporarily sheared.
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