alengyel

From what I understand, it raises the octane 10 points by slowing the flame front. Plus the cooling affect in the manifold it makes things run smooter and stronger.

RAD951

There were tests that showed that the actual temperature of the exhaust gases were lowered by like 60 degrees when water injection was used. Water/alchohol itself won't increase horsepower, its the ability to run the timing advanced to its fullest and lowering intake temperature, and keeping the engine most importantly from detonation. Rule of thump is for every 1 degree of change in timing results in a 5 hp increase. Also for every + - 10 degrees of intake temps equals to 5 hp.

911pcars

Water does not increase octane as it is not a fuel. However, by spraying it inside the combustion chambers, the effect is the same as using high octane racing fuel to prevent detonation. The water lowers the heat of the intake charge to delay the onset of detonation and thus allows the tuner to either increase ignition timing, raise boost pressure and/or raise compression ratio to higher levels for more power. Since water is not a fuel, air/fuel mixtures must be correct under boost conditions otherwise damage will occur.

Sherwood Lee
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