I thought I’d add this little bit of family history-
My grandfather was a WW1 aircraft mechanic, he told me that he made up a water vapor injection system so water vapor could be drawn into the air intake of the engine.
I don’t remember if he even detailed what he used or how he kept the intake from getting a gulp of water.
But I do remember he said that the water vapor helped with fuel economy, engine performance, engines ran cooler, and were cleaner because of a more complete combustion.
He said think about it, doesn’t your car run better in fog or a heavy rain?
Years later during some “lean times” I took a mason jar, and punched 2 holes in the lid.
In one hole I put a piece of copper pipe long enough to almost reach the bottom of the jar, the other end was open to atmosphere.
I put a valve in the other hole and ran a line from the valve to a vacuum line from the carburetor of my Ford van.
With water in the mason jar the carburetor drew air from atmosphere through the water
making bubbles (the amount was controlled by the valve) then drawn into the carburetor and mixed with more oxygen and fuel vapors.
Now from what I remember my little science project did result in a bit more fuel economy, but most notable was the van ran better, better throttle response.
I was pretty pleased with what looked like a miniature moonshine still, and in the winter I would add an ounce or two of gas line anti freeze.