I made a Sun engine from castings - drawings date from 1963. Goes like the clappers! - Had it in a boat, but was too heavy so bought a Star engine - half the weight but with different gearing still powers the boat. These sell at £200 plus in working order in the UK. The Sirius is double the size of the Sun (used to power generator sets for radio battery recharging - dropped to French resistance during WW2). Now going for £4 - 500. - and £thousands for the WW2 generator set in working order. Boat (small launch) engines go for £3~5000.
K2
K2