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Old 11-26-2001, 08:01 AM   #5
P10DET
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Quote:
Originally posted by A380Driver
When you add a little water to the mixture, it makes the intake air more dense, therefore providing more power...
This is wrong. Water does not add more power, it makes less.

Using water injection in a normally aspirated car is a waste because it will make less power. The water displaces air and fuel and reduces power output.

The reason it works so well on a turbocharged car is they can add more boost and other tuning tricks to get more power than is lost. In a turbocharged car, the temperature of the mixture entering the engine is critical since it heavily affects detonation. All cars hate detonation, but especially turbocharged cars. The water injection lowers the intake temps and this allows you to run more boost and/or ignition timing.

The bottom line is, it will make a NA car make less power, but it can make a turbocharged car make more power because you and do things with a turbocharged car to more than make up for water. Remember, with NA, the water displaces fuel and air, but with a turbo, you just raise the boost and you can keep packing in more fuel and air.
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