If u did not missed ur Chemistry and Physics class even in High School u would agree on this.
U want to research and go ahead and prove me wrong (If u can becuase those are facts w/ no B.S.). There are some more stuff that goes w/ oil mixture too, which I did not mention this are.
How long is the race (Endurance race 1 to 2 hours or 5 to 10 min heat) ?
Which track ? Bigger or smaller track.
Off course modifying shims on the heat sink is another story, because the question was. What are the effect of the different oil mixture?
If ur still confuse on my statement, I advise u to start reading first then ask questions to Rody or Arturo Carbonelli. I really suggest ask Rody because Rody replies quickly. But reading would not hurt !!!!! Instead it will give knowledge and understanding hehehe!!
BTW: Let me hear ur side of the story. Answer the question from above w/ ur own words and prove ur statement.