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DIY water injection

Posted: Fri May 27, 2005 11:43 am
by Junkers
Image

What do you guys think? I might have a shot at making one this weekend.

How much spray should come out aproximatley?

Re: DIY water injection

Posted: Fri May 27, 2005 12:18 pm
by galagaza
StazzyBabyYeah wrote:Image

What do you guys think? I might have a shot at making one this weekend.

How much spray should come out aproximatley?

Personally I would put the nozzle on the pressure side of the turbine and use a small electric pump.. Im no fan of particles in turbines doing 150000RPM.. But thats just me, I guess it could work......

Posted: Fri May 27, 2005 2:56 pm
by StarionPWR
If you spray the water before the turbine you will chew out the compressor wheel. I think just before the throttle body is the common place to put the spray nozzle and use a pessure switch to turn the pump on when there is a certain amount of boost pressure.
The main thing is to get a spray nozzle that sprays a fine mist, basically atomising the water.
Ive seen a few home made ones that have worked fine.
Usually run 50/50 meths and water from memory.

Posted: Fri May 27, 2005 3:37 pm
by hoongirl
The one on my car has the water/methanol mix going in just before the throttle body and you can choose what boost level it comes on at.

I'm pretty sure it used a special water injector thingy to spray the smallest possible drops so it would all evaporate very quickly.

Although afaik the one on my car was sourced from the US - not home made.

Posted: Fri May 27, 2005 7:12 pm
by WidebodyWoody
Just before the Throttle Body for sure

Posted: Fri May 27, 2005 9:41 pm
by Junkers
WidebodyWoody wrote:Just before the Throttle Body for sure
That was the plan anyway, I don't think it'd be as effecient spraying into the hot turbo.

As you can tell starionpwr this one does not require a pump (reason why I like it), it only works when boost is on because pressure will force the water to exit the reservoir via it's only path, the spray nozzle.

Seems nice and simple, shouldn't cost to much.

All you people with water injection systems, did you notice much of a difference after install?

Posted: Fri May 27, 2005 9:45 pm
by bazeng
nop bad idea..
i'd go after the compressor...

http://www.turbomirage.com/water.html

Posted: Sat May 28, 2005 12:02 am
by iXNAY
has anyone done "ALCOHOL INJECTION"?

Posted: Sat May 28, 2005 12:08 am
by Abalistic
Honest, you will not hurt the compressor wheel if you spray fine into the inlet,
the turbo will thank you for it and reduce the temps.
A.

Posted: Sat May 28, 2005 4:47 am
by FuelinjectionPro
iXNAY wrote:has anyone done "ALCOHOL INJECTION"?
We use water injection on our car and have found it to be a easy and low cost way to run more boost. We have been able to run about 5 psi more on pump gas. It is also good for the engine as it smooths combustion and cleans as well!
Some notes:
One thing to keep in mind, water or water/alcohol(up 50-50 mix) injection is not the same as alcohol only injection.
Water is a real detonation supressor, for it to work it must not be vaporized before it gets into the cylinder, but needs to to be in very fine droplets. It is true that it may cool the intake air some but this is not the main thing, it is the way it helps control detonation INSIDE the cylinder during combustion.
Alcohol( high in octane) added to the water provides some cooling and fuel to burn, a mixture of over 50% alcohol will not improve the effect.
Alcohol injected by itself will cool the intake air and rase the total octane of the air /fuel mixture, but does not control detonation the same way as water does.

Posted: Sat May 28, 2005 8:16 am
by iXNAY
so has anyone on here sucessfully done a water, water/alcohol home made injection system that has worked?
and were have people decided to inject it, in the actual throttle body?

Posted: Sat May 28, 2005 9:09 am
by fr335tyl3r
see the above link to the turbo mirage site ixnay. It would seem that the most common place to do water/alcohol injection in the intake would be just before the throttle body.

Any more thoughts on whether or not it is a good idea to spray water before your compressor wheel? Reading from a few sites, it seems like this is ok, but not a good idea if you already have an intercooler (if you have an IC it is suggested that you should either spray water onto the exterior of the IC or do the spray into the intake closer to the throttle body).

Posted: Sat May 28, 2005 9:54 am
by Chryzla
ive never understood why... getting water in the cylinders isnt exactly the brightest of ideas

Posted: Sat May 28, 2005 10:08 am
by Junkers
It has something to do with water droplets absorbing heat better than air (hence water to air intercoolers), all that happens from my understanding is that the droplets absorb the heat and turn to steam and are forced out on the exhuast cycle.

Posted: Sat May 28, 2005 10:20 am
by bazeng
i would do it right after the intercooler, this would give the water the most time to vaporize...

the point of water injection is to lower air time.. by the time the water gets to the engine, it wont be a liquid anymore,

its best after the cooler because the air would have gone through the 1st stage of cooling meaning that you would probably reach a cooler temp, whereas if u go before the cooler, the air would probably be already cooled enough that the intercooler isn't required.. (ambient temp)

the intecooler would only get the air at best to ambient temp, whereas water injection if u used say ice / meth , you could reach a lower than ambient temp