>>What brand is the engine before it becomes a Taurus?

They do not come from any brand. They are not a conversion. Athough they use some "off the shelf" parts, they are designed from the ground up to be a gas R/C engine.

Taurus cylinders come from Mahle. Mahle OEM's cylinders for many manufacturer's for many applications. I would assume the piston and rod come from the same source.