[fso301]

Thanks. I still don’t understand how pure water increases horsepower.

When the engine is heavily loaded and running at full power, injecting water into the fuel-air mixture, or directly into the cylinder cools the combustion chamber. A cooler combustion chamber permits a denser fuel-air mix and can reduce knocking.

My understanding of water injection is that it doesn't provide much of a benefit at normal power settings.

[Rebelbase]

That makes sense. Thanks.