Viscosity for open track car

[PeteL]

I open track my '00 LS1 Camaro. I don't have an oil temp gauge on my car but others have reported temps approaching 300 F in this application. Temps that high scare me, so I have been using M1 15w-50 as a precaution. Is this too high a viscosity as some on other boards claim? I'm concerned about longevity and I'm willing to sacrifice a few hp to achieve it.

BTW did a search but couldn't find anything this specific.

 

[Dominic]

The reason people run a higher viscocity in a race engine, which can see those temps, is that the oil thins as it is heated.

The 30wt is measured at 100C, and so is the 50wt grade. However at much higher temps, the 50wt now has the effective viscocity of SAE30 @ 100C. (Someone correct me if I'm wrong).

You could probably get by with a slightly thinner oil, maybe a 40wt, especially if you have an oil cooler.

 

[pedaltothemetal]

Don't forget high rpms and loads shear down the oil at the bearings. So 15w50 is what you need. Or you can to 10w40 Redline. It shears down less and may be equal to the 15w50 Mobile 1 under racing stresses.
Also mentioned above, synthetics can take higher temperatures than dino and not break down as quickly.

Leo

[ May 21, 2003, 02:53 PM: Message edited by: pedaltothemetal ]