The guide will forward all correspondence to Mr. Rogers. The claim is liquid nitrogen, when expanded to its gaseous state, expands by 960 times its volume. That translates to pressure which drives an air motor to run the vehicle. As the liquid nitrogen passes through this expansion tubing, the ambient heat will cause the liquid to change to a gas through a phase change. Liquid nitrogen expands by 980 times its volume when changing from a liquid to a gas.
Expansion means pressure which translates to power.
An air motor is kind of like a paddle wheel on an old style riverboat. As compressed air is blown against the paddles, a shaft is spun which drives whatever is attached, in this case, the transmission of a vehicle. Boese said that only a slight modification to the air motor was necessary to make the it run perfectly with the expanded and very cool nitrogen gas. There is another paper on a fellow in Costa Rica or Puerto Rico who also has an air engine. When I find that info, I will post it also, though as I recall, it doesn't give the same quality of information which Mr. Rogers does in his interview.