simplistic uniflo steam engine pretty easy to make and only one moving part ehe. would say its probably noisy to run.
Easy to make fun to learn about, can be made from old cd’s . some of my plans for it were to use this for waste recovery in the oilfield on flare stacks to generate power and get green credits back for some of the oil companies. if you shield half of a turbine with even just 2 or 3 disk it would work well for a flow meter aswell rather than using turbines as flowmeters, less maintenance less damage and plugging from asphaltenes .
chevy’s were considered the dime a dozen mechanics dream back in the day because of the interchangability / cost of the parts.
the 350 was very popular and i have herd of these being converted into pumps and also converted to run on compressed air. one can usually replace with a big block without any modifications other than bolt mount position and larger radiator.