[JerryBurks]

At 14" of mercury at 6000 RPM that blower might take 100HP or more.

You might look at the Roots style blower for a example of HP draw.

45 URAI Roots Style Blower | REP Inc

The PDF will show the HP curves. The flow verses vacuum is about the same for all rotary lobe pumps.

You can still use the pump you have but I would think you may only be able to drive it at 500 RPM or so depending on the vacuum pressure you need.

I do have a extra Roots 33 blower that has been sitting out for a few years. I don't plan on using it and it is rusted inside so it wont be good for hi vacuum but I would take $30.00 for it.
I'm in Phoenix.
Good luck.

Dave

Thanks for the link! I was looking for such charts. The info from Eaton has only the efficiency and volume chart but lacks the power info for vacuum operation. I compared a similar size from that company to my Eaton blower and it looks indeed like I would need about 6-7 hp to run at 6000 rpm. Unfortunately I do not have that much electric power available in the shop. But I could get a 3hp motor and run it at lower speed. I will give it a try. So far I only spun it with a 1 hp hand drill for testing.

.......As a hold down, you may have bypass some air to provide cooling.......

Yes, that is surely necessary. I may also have to route the motor fan air flow across the supercharger for additional cooling. Fortunately they are built to survive running hot on top of an automotive engine. But that is just part of the experiment.

.......By the way does it need oil flowing through it?

.
No, it has a built-in oil reservoir for the bearings and gears. The blower rotors run dry.