I recently had a chat with a member of one of the leading Bonneville
roadster teams. He said they use a dry-sump system which keeps 100 psi
in the engine at all times, and always use Valvoline
Racing(non-synthetic) 20w-50, but they have a heater for the oil tank
and get it to about 200 degrees F before they fire the car up to run it.
This is with an extremely high-output and high rpm smallblock Chevy.
I use 5w-30 Motorcraft non-synthetic in my Ardun at ECTA and it works
fine for me. I feel with this low-cold-viscosity oil, I don't have to
worry about getting it real hot. It works fine for me, no trouble. It
is a fact that cold 20w-50 oil is pretty thick, and I can see that it
might not be able to get through the crank to the rod bearings at high
rpm; and cause the trouble that Bryan described.
Obviously personal taste has a lot to do with what oil you like to run
in your racer... Bill H.
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