There have been quite a few questions and PM’s about water injection recently, so I thought I would do a quick write up on it and create a thread where questions and answers for it can go. I am not an expert in water injection, but I will try to answer any questions that I can.

What does water injection do?
The pain purpose of water injection is to prevent detonation (also known as knock). Detonation occurs when the air/fuel mixture in the engine ignites prematurely or does not burn correctly and evenly. This causes the fuel to burn explosively, and creates a massive increase in pressure in the combustion chamber. These increased pressures can severely damage an engine. When water is injected into the engine along with air and fuel, it allows for a more efficient and even burn. This also reduces temperatures and creates denser air in the engine.

How does it work?
Any water injection system will include a pump, an injector, a pressure sensor, and an air inlet sensor (on some cars the stock sensor can be used). The injector is placed before air enters the engine (usually on the cold side pipe for srt-4’s, or through direct port injection in the intake manifold). The intake air sensor tells the pump when to start injecting water based upon a pre-set temperature (often 40C and while in positive boost).

What does methanol do?
While pure water is best to reduce knock, but methanol is sometimes added to the mixture to increase power output.

Why use water injection?
Water injection is beneficial for a number of reasons. The first is to prevent detonation or knock, which can be very harmful to engines. This is especially useful in high-boost cars where octane ratings are in question, or higher octane fuel is not readily available. The use of water injection allows a lower octane rating to be used. Secondly, water injection reduces exhaust gas temperatures (EGT). Third, water injection increases power output.

Other points:
Water injection on its own is very safe. The kits available today are complete and easy to use, and allow for multiple stages or progressions to be utilized depending on the needs of the owner. Water injection has been used since the 1930’s in WWII airplanes, and has proven itself effective. Water/Methanol injection has also been used for long periods of time, however this is for more advanced users. Incorrect mixtures of water and methanol can lead to dangerous air/fuel ratios.

Dyno Results:
91cavigt saw an increase of 14 fwhp and an increase of 8 degrees of timing, while showing a reduction of air intake temperature from 105 to 87 degrees. This is typical for stock turbo cars.

Some dealers for water injection:
SnowPerformance
Aquamist
Devil’s Own
Cooling Mist

 

awesome post psi that cleared up alot and i even liked that you added the dyno results on the stock car with it .


thanks,
micah

 

why dont you have it psi?

 

i will later on this summer. i spent all my cash on my turbo and suspension upgrades for now, once the credit card bills are under control i'll be getting a dual stage set up with some nice goodies from snow performance!

 

duel stage arrrrgh i only got the single stage oh well there always somebody upstaging ya.lol

 

Do you think that it is worth putting on a stock SRT-4 Or should be considered on a modded car more than a stock one??

Thanks
Andrew

 

w/i is helpful on any forced induction car. if you ar emostly stock, there are other things that you can be spending your money on, i wouldn't put this at the top of the list. as the car becomes more modded, then it is more effective.

 

Psi chick. I see you say dual stage. If your planning on using this for HOM simulation, as I had planned, I would recommend a progressive system. I really think it's more suited to HOM than a staged system.

For newbie info.

Dual = sprays XX amount of water when triggered by a boost switch. Hit the limit on the switch, say 5=7 psi, it turns on. A second boost switch set higher, say 14 psi, turns on another nozzle, adding more water. So figure two plateaus/

Progressive = Once triggered, it begins to spray, but as boost rises, so does pump pressure, increasing amount sprayed. So instead of ___...------ you get a ramped effect, with no rapid change /

Personally, I would wait a little and see how devilowns works out, he's looking pretty good.

 

Good stuff Chick thanks!!!

 

couldnt help myself when i went to speed gear to see how much they would install my w/i system when it comes in i bought a new toy its called the hyper hotinazma voltage system which is an import only item in the states havent installed it yet but will keep everybody informed when install is complete and drivability results.