Checked:
· does heat-exchanging the used up steam with the water before the boiler pre-warm the boiler water? (Just like how exhaust is also hot)
· YES. Pre-warmed water improves boiler efficiency.


New Things to check:
· Can you just put the entire water tank on the same cooling loop as the steam boiler to 'pre-heat' all of the water even before the boiler gets to it? (Not something you can do IRL, but maybe a possibility)

Things to check with boilers:
· does heat-exchanging the used up steam with the water before the boiler pre-warm the boiler water? (Just like how exhaust is also hot)
· could you also use exhaust alongside warming up the boiler to warm up the water tanks?
· does creating a vacuum in the engine compartment effect heat efficiency?

Other possible versions:
· Turboprop on top, dont use a jet engine, but have a medium turbine + turboprop.
· Small Ducted fans for above 80m/s to improve speed. With the rails, 70m/s is already very precarious, especially with cars that like to explode.

Note:
· Speed is not the objective, but it is always fun to have other versions for the multi-role position.