Quote:

Not saying you guys don't know your stuff, but call Joe Gibbs.

http://www.joegibbsracingoil.com/

They've spent many many dollars on oils and finding out what works best with different clearances, ring packages, etc... They know their stuff, I got to sit through one of their seminars and I was impressed with the knowledge they had.


Joe Gibbs makes excellent oil, but has less detergents. Brad Penn is just as good, is much cheaper, and has a lot more detergents.
My engine builder has used both, and said they are about the same quality wise.
That's why he recommends Brad Penn. I use their 20w50 in summer, and now their 15w40 in spring and fall.