just curious what oil is used on pro charger, whipple etc? is this special oil and what grade is used and how often is it changed?

The older ProCharger models used the oil supplied from the engine. Don't know on the self contained models.

Check with the Supercharger builder they
should be able to tell you
the best oil for their units.
Myself I have had very good luck with the Oil
used for the bearings in Jet Motors,You can find it at most airports or Jet fuel dealers.
Mike J.

I've been told to use Mercruiser outdrive lube in my B&Ms..

Whipples use 5w-50 100% synthetic oil such as Syntec 5w-50.
Dave