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Just ran across some info on a car (not air cooled) running water injection. Got me thinking, never hear of the high HP air cooled cars running it? Do they run it and I just missed it? Or is it a secret not to be talked about?

Just curious since it sounds like it raises compression - good for racing and street performance.

And also lowers emissions - can help in the long run on the street.

Here is some basic info I found on it:

Water injection (engines)

Water injection, also known as anti-detonant injection, is a method for cooling the combustion chambers of engines by adding water to the incoming fuel-air mixture, allowing for greater compression ratios and largely eliminating the problem of engine knocking (detonation). This effectively increases the octane rating of the fuel, meaning that performance gains can be obtained when used in conjunction with a supercharger or turbocharger, altered spark ignition timing, and other modifications.

Composition of fluid

Many water injection systems use a mixture of water and alcohol (approximately 50/50), with trace amounts of water-soluble oil. The water provides the primary cooling effect due to its great density and high heat absorption properties. The alcohol is combustible, and also serves as an antifreeze for the water. The purpose of the oil is to prevent corrosion of water injection and fuel system components. [1] Because the alcohol mixed into the injection solution is often methanol (CH3OH), the system is known as methanol-water injection, or MW50. In the United States, the system is commonly referred to as anti-detonant injection, or ADI.

Effects

In a piston engine, the initial injection of water cools the fuel-air mixture somewhat, which increases its density and hence the amount of mixture that enters the cylinder. But the greater effect comes later during combustion when the water takes in significant amounts of heat energy as it converts from liquid to gas (steam). This increases piston pressure (torque), reduces peak temperature and resultant NOx formation, and reduces the amount of heat energy absorbed into the cylinder walls. The alcohol in the mixture burns, but at a much slower rate than gasoline. The net result is that the combustion process happens slower, preventing the destructive supersonic shockwave characteristic of detonation.

When used in a turbine engine, the effects are similar, except that preventing detonation is not the primary goal. Water is normally injected either at the compressor inlet or in the diffuser just before the combustion chambers. Adding water increases the mass being accelerated out of the engine, increasing thrust, but it also serves to cool the turbines. Since temperature is normally the limiting factor in turbine engine performance at low altitudes, the cooling effect allows the engines to be run at a higher RPM with more fuel injected and more thrust created without overheating. [2] The drawback of the system is that injecting water quenches the flame in the combustion chambers somewhat, as there is no way to cool the engine parts without cooling the flame accidentally. This leads to unburned fuel out the exhaust and a characteristic trail of black smoke.

Fuel economy can be improved with water injection, although the effect on most engines with no other modification, like leaning out the mixture, appears to be rather limited or even negligible in some cases.

Some degree of control over the water injection is important. It needs to be injected only when the engine is heavily loaded and the throttle is wide open. Otherwise injecting water may simply drown the engine and cause it to quit.

Use in automobiles

A limited number of road vehicles with large-displacement engines from manufacturers such as Chrysler have included water injection. Saab offered water injection for the Saab 99 Turbo. Subaru has also offered a factory water injection system on their high performance model the Impreza WRX STI. With the introduction of the intercooler the interest in water injection disappeared, but today, water injection is also of interest because it can potentially decrease nitrogen oxide (NOx) emissions in exhaust. The most common use of water injection today is vehicles with aftermarket forced induction systems such as turbochargers or superchargers, particularly those used for drag racing and illegal street racing.[citation needed]

Here is a website about water injection, the history and race use

http://www.rbracing-rsr.com/waterinjection.html


And here is a High Performance Water/Methanol kit for HIGH HP output


http://www.coolingmist.com/

Just curious because it all sounds good. Especially for the turbo guys!!
 

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so67vw said:
I attempted to talk about this on Cal-look but the closed minded genius' there shot it down.... I didn't tell them that I've seen the results myself.... I just let them shoot off BS about how it doesn't....
Thats why your here ;D I hope to keep it open to any opinions and ideas!

If you don't like the Hydro injection then don't use it! But don't bag on others who want to try it.


Glad to have you sharing your opinions here!!
 

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I'm very interested in hearing some results! Please get back to us with some details if you don't mind, I love hearing about this kinda stuff!
 

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in ww2 P47 andP51 mustangs used meth injectors in full military power , big gain in power enough to make the differance in a dog fight.
 

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Turbo Bob Hemphill runs it and ALWAYS has.
Thats one of the reasons he makes 250+ hp on a daily driver/race car.
Oh yeah and he NEVER breaks it (except the trans).
 

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Marty Staggs said:
Turbo Bob Hemphill runs it and ALWAYS has.
Thats one of the reasons he makes 250+ hp on a daily driver/race car.
Oh yeah and he NEVER breaks it (except the trans).
I am really surprised more people don't do exactly as Bob has done. His power plant has been very impressive. Next time you see Bob ask him about his motor and you will be surprised at how reliable it is. Very impressive indeed.
 

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I use the 1S system from Aquamist,have tested it this summer and it works.I have still just played with a small jet,but the first time we tested my speed on the 1/8 mile went up from 112 mph to 117 without any other changes.The methanol/water mix was 25/75.You'll find lots of info regarding water injection on their website and their forum..

http://www.aquamist.co.uk/

http://www.aquamist.co.uk/phpBB2/

Regards, Tekken
 

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Marty Staggs said:
I have known Bob for almost 2o years. I know all about his combination etc. ;)
I wasn't meaning you should ask him. LOL I was expressing how open and approachable Bob is. When I grow up I want to have a motor just like Bobs! You know anyone that can build anything like that? ;D
 

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pfer10 said:
I wasn't meaning you should ask him. LOL I was expressing how open and approachable Bob is. When I grow up I want to have a motor just like Bobs! You know anyone that can build anything like that? ;D
;D
 

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Thanks guys.

I use the Aquamist 1S system and use a 50/50 mix of distilled water and methanol.
Methanol is the fuel of choice, not Ethanol and only up to 50% amount.

I found out using pump gas that I got 3 extra PSI boost using water/meth injection, 10 PSI total on pump with my engine combo.

I did not find any improvement at high boost (24) & C-16 fuel, any quicker ET or MPH, but I am sure it does not hurt to use it, as I do while racing. Other engine combos will act differently, so try it out.
 

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I run the AEM Universal injection kit on my turbo'd 2387. I mix 50/50 water and denatured alcohol and spray it directly into the Holley on the drawthrough setup.
 

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Dillution suppoesedly makes it not evaporate as fast.

Running 50/50 with premium gas is like having C16 in your tank

You can also run the winter mix of windshield wiper fluid (-32)

I've had a system on my car since the beginning and you can look at the picture at the left to see what happens when you accidently run out at boost (24lbs)
 

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The heat of vaporization is much higher for water if I remember my chemistry right. So for a given volume, water removes much more heat from the combustion chamber as it changes phases from a liquid to a gas. The methanol increases the octane value.
 

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2stroke said:
im running straight methanol in mine, why are you guys diluting it? cost?
"WATER? Water exists mainly in a liquid state because that is its most stable inter-molecular structure. When we apply heat energy to it, its molecules begin to expand: a great deal of heat is absorbed during this process owing to water's specific heat capacity - approximately 4.2kJ/(kg.K). When the water changes from the liquid to gas state, large amount of heat energy is consumed in sustaining the process. The latent heat of evaporation is 2256kJ/kg, approximately six times more than gasoline! "
http://www.aquamist.co.uk/dc/dc.html

"9. Why is Methanol better?
Methanol itself has a octane number of 113. Not only does it improve your fuel quality, it will also give you a better intercooling effect in the inlet tract.

10. What is the maximum alcohol/ water ratio I should use?
No more than 50%, otherwise you will increase the cylinder temperature rather than reducing it. Beyond that ratio, onset of detonation is more likely. Methanol freezes at -96 deg. C, 50% mixture will stop the mixture from freezing at around -40 deg.C. "

http://www.aquamist.co.uk/rescr/rescr.html
 
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