The giant rotor was from an engine built by Curtis Wright. It was used for driving industrial pumps for natural gas and other things.

Not a Mazda.

They also built a rotary powered first gen Mustang with their RC-120 rotary engine. (120 cubic inches, 140 hp)

 

wasnt it for pumping some form of oil, and the engine itsself ran off the oil it was pumping

 

Notice the chamfers on the huge rotor, just like Mazda does for the RENESIS and a few members on here have done in their own engines.

 

I believe that the first ones were designed to pump, and run on natural gas, then they started building crude oil powered ones.

I searched and found a pic of the rotary powered mustang, I think. The one I saw in the Rotary engine book had a slightly different air filter housing, but looked the same. And it was 180 something horsepower, not 140.