umm... I think you are making this too hard
water injectors are old school - like WWII propeller war bird old
many of the real high performers had water injection
Why does it work?
a little sprits of water goes in liquid and boils in combustion
and comes out a big puff of hot steam
- the steam comes out hundreds of times the size of the liquid water that went in
it also evens out the temperature spike of combustion - gentler but stronger bang
- all because the latent heat of water is freaking hugh
why is it clean inside - because you are steaming the cylinders
Normally This works best for engines and high throttle settings
a car at cruise or idle power is not going to see much benefit
but with lean burn maybe it would help
you could probably test with a rather primitive set up (spray nozzle in intake)
Go for it
