Well I guess will be very easy to modify an engine to run on water only.
We need a Bmw with common rail technology, than you need to take out the diesel pump...
Now you need a source of 220v 4 amps. Construct a cell having two plates witch withstand at least 300psig of pressure with a metal membrane to let the hydrogen to come out of it pure just the h2...
Than the h2 will get into the motor probably together with the air to be compressed, than at the max pressure point, water will be injected at the right temperature and pressure.. Than a mean of burning the h2 inside the engine can be found, a spark...
The cylinders and pistons should be made of copper content metal, to be able to absorb more energy from the ambient and to give more of this energy during the next cycles.
I think that the electricity needed to pressurize the water and keep it at the right temperature will not exceed 600w.
With 1200°c inside the engine the water will become vapor expanded. Thus will extract more energy from ambient in my opinion. You just need to make the droplets to become very small so they can redly absorb more energy while the temperature is still very high.
Probably the h2 is not even needed.
The procedure to make it run would be to heat the water and inject using initially a pump, when the right pressure and temperature is found we can design a cell witch will do it all in once.
As water can absorb a lot of energy and its expansion ratio is 1800, i think it can be easily made to self run. Witch is hard with only air.
