The questions of water injection....

[Omega_5]

I;m not sure if this has been posted before, but it's a good idea. I've found that there are alot of people who are quite new to the idea of water injection... actually alot of people seem to think that spraying water into and engine will kill it.
Well, water injection is normally used by Talon/Eclipse/Laser owners running high boost. The theory of it is that it decreases knocking in an engine. (Foe those that don't know), knocking is the pre-detination of fuel in an engine, usually from heat or compression. Water can be injected into the engine to lower the detination point of the fuel being used. Now keep in mind that running higher octance fuel also lowers detination (due to the lower det. point).
Now the method i will describe, as stated above, is commonly used on Eagle Talons. I have seen many variations on this set-up, but prefer the design my friend made (and i helped install).
After the turbocharger(s), air flow meter (MAF/MAP) and throttle body in a car, there is a plenum, or pressure air box before the engine. In this air box, you must drill a hole and fit an screw in an injector, keep in mind that the air box must remain air tight and that the injector must spray in a manner that will allow the water to be carried into the engine. A pump (a fuel pump works ok) must feed the injector with water at a certain pressure level. A tubing system must be ran a tank (to hold the water) to the pump, and to the injector. Remember that the tubing MUST be resistant to rust (there will be water running through is tube). Now a boost sensor should be hooked up within the intake system, so that when your car reached a high boost level, (just below the stock max) your water injection system will turn on (you don't want water being sprayed into the engine at an idle). As a saftey measure, the knock sensor on the car should be hooked up to a pressure valve, which will open the BOV on your turbo(s) if detenation occurs. The reason for this, is that if debri is caught in the injector, you car will run VERY lean, and cause damage to your engine, especially if your will be running high boost.
There are websites that give more detailed descriptions of this procedure. If you are serious about installing this sytem, please consult those websites first.
A variation to this, is running two injectors. For example, my buddy has his first injector turn on at 8psi, and the second turn on at 14psi. So until 8psi he runs no water, from 8psi til 14 psi he runs one injector, and from 14psi to 17psi (his max) he runs two injectors.
This is an easy and cheap modification to any boosted car. Keep in mind though, that if you plan in running high boost, you fuel pump and fuel deliverly system should still be upgraded, and that you shouldn't run you turbo at overkill. This is mainly for if you want power from pump gas.

[Sluttypatton]

I personally dislike water injection for most applications. I think it is just a band aid for an improperly set up car. I admit that there are cases where maximum effort cars are properly set up and they make use of water injection to squeeze out a little extra detonation tolerance, and I don't have a problem with that. I just object to many people installing water injection systems rather than doing the job properly.

You have an interesting post, but I think it would be a good idea to correct a few little details.

Water injection works by decreasing the charge air temperature. Water has a fairly high specific heat (4.184 J/(g *C)) meaning that it removes a large amount of thermal energy from the charge air while only changing temperature slightly it's self. This makes it great for cooling the charge air, but a properly sized intercooler is a better alternative.

If debris were to get caught in the water injector, the engine would not run lean as the injector is not responsible for delivering any of the engines required fuel supply, it only delivers atomized water to cool the charge air. The air/fuel ratio would remain identical to what it previously was and any resulting detonation would be due to the hotter charge air rather than an improper a/f ratio.

[Omega_5]

thanks for the additions.
I should also add that using a blend of alchol and water (aka windshield washer fluid...lol), in some case is a better idea. The link below leads to a discussion on that topic.

http://www.automotiveforums.com/vbul...d.php?t=396368

[guitarXgeek]

I'm pasting my post from the DSM forums about water injection in here as well...


Oh boy, so much information about water injection (WI from now on) that it'd take a couple pages to get most of it down I guess I'll start off by just laying out some of the basic concepts/ideas/reasons behind WI.

First off, I'd like to mention that WI has been around for a LONG time. The turbo buick guys I think started the whole WI thing way back in the day, and for good reason too. Since water cools so incredibly well (hence the reason you use it partly as coolant for the motor ), it has the ability to almost completely eliminate knock/detonation caused from excessive heat in the combustion chamber - which happens to be the main cause for detonation in turbocharged motors.

Also, the continuous use of water injection actually cleans the entire intake stream, the valve tops, and the combustion chamber. I'm sure some of you have heard of people using Seafoam to clean the carbon out of the combustion chamber, right? Well, before Seafoam came about, people used small amounts of water to clean the carbon build-up in the combustion chamber. I don't know exactly what property of water allows this to happen, but it works VERY well. So not only do you get the benefits of hardcore knock suppression, you can rest assured that there are no carbon hot-spots inside the combustion chamber causing knock/detonation

The whole reason WI works so well with turbocharged vehicles is water's latent heat properties. Basically, water absorbs heat extremely well, especially upon evaporization. A small nozzle is placed somewhere along the intake path on the intercooler piping. A common place is roughly 6-10" or so from the throttle body. Now, remember that the temperature of the charged air can reach well over 250 degrees F. The water is injected into the intercooler piping via the small nozzle (which is sized to the amount of fuel available, usually %15 of the total amount of fuel available). The water is sprayed into an ultra-fine mist and almost IMMEDIATELY it is evaporated by the hot charge air. Now water's latent heat of evaporization comes into play. As the water hits the intake stream, massive amounts of heat is absorbed by the water and is almost immediately taken away as the water evaporates. Thus, a MUCH MUCH cooler intake charge!

As for me, I plan to take FULL advantage of this wonderful idea and use a two-nozzle water injection system on my GSX. I actually plan to put a very small nozzle just before the intercooler (the stock SMIC) and a larger one pre-throttle body. My reasoning for keeping the stock SMIC is for the sleeper look, as well as the whole money issue The only thing limiting me on the stock SMIC then would be the airflow restriction of that POS.

I'm sure you're wondering why I opted for a small nozzle pre-intercooler, since that would effectively reduce the entire purpose of the intercooler. However, since the stock SMIC likes to heat soak extrememly quick, the small amount of water injected just before it will keep the heatsoak to an absolute minimum! I even know of people in extremely hot climates that use a small nozzle just before their front-mount intercooler just to help combat heat soak.

Another popular thing to do is for people to inject is a mix of water and alcohol (methanol, to be exact). The magic % from what I've read is 25% water and 75% methanol. The reason for using methanol is it's ability to compensate for low-octane fuel. Methanol in itself has the ability to effectively "raise" the overall octane of fuel mixture (it doesn't literally raise the octane, but it has the same effect) allowing you to lean out a little more and raise the boost a little more. It's kinda the same effect as running "race gas" all the time. Another reason is that methanol has much better combustable properties than water, which is why a good mix of the two is pure sex. You get the heat reduction properties from water, and the "octane raising" properties from methanol. I've seen some results from users on the dsmlink forums, and I'm further impressed each time I see results!

The one downfall to methanol is that it is quite corrosive, so extra care must be taken with regard to the pump, container, and lines. I should also note that only distilled water and/or "smurf piss" (winshield washer fluid - 49% water, 49% methanol, 2% blue dye) should be used for water injection. I have heard, though, that the smurf piss has a tendency to clog the nozzles.

There is a LOT more information about water injection out there, especially on dsmtuners.com. But I think it would be good to get a base of information on here, though. I think I just covered the tip of the iceberg, so someone else may chime in if they like

Here are some links to a couple vendors that sell nothing but water injection kits. Lots of good information there..

www.coolingmist.com
www.aquamist.co.uk/


-Matt

P.S. Here is a thread on dsmtuners.com that shows the wonderful results of pure water injection... http://www.dsmtuners.com/forums/showthread.php?t=41303

[nissanfanatic]

I'm not a fan of WI either. I also agree its a band aid for an improper setup. I think I'd just upgrade my intercooler.

[Omega_5]

thanks guitarXgeek for re-posting that bit of info... it's always good to have a second opinion...

[guitarXgeek]

Originally Posted by nissanfanatic

I'm not a fan of WI either. I also agree its a band aid for an improper setup. I think I'd just upgrade my intercooler.

That's a valid point, to an extent. You do realize that your typical air-to-air front-mount intercooler can only do so much cooling, right? I've witnessed FIRST HAND the results of water injection on a VERY well setup car equipped with a Spearco 2-216 core (arguably one of the best/most popular air-to-air cores on the market) and was throroughly shocked. Even this high quality bar/plate intercooler saw HUGE benefits from a water injection system. After adding a 50/50 methanol/water mix, the car ran EVEN BETTER. He was able to run a couple lbs more boost and 1-2 more degrees of timing advance on pump 93 octane. You call that a bandaid? Hah I call it smart.

You simply can not deny the large gains to be had from water/alcohol injection on any turbocharged car equipped with an air-to-air intercooler. The intercooler will only get so close to ambient temps, and the water injection can nail it on the head. There's a reason that the old turbo buick guys ran it back in the day, and it sure as hell wasn't as a "bandaid" I can garauntee that ANY properly setup and tuned turbocharged motor will see dramatic gains from a water/alcohol injection system (assuming an air-to-air intercooler is used. the benefits are arguable on setups using water-to-air coolers).

Originally Posted by Sluttypatton

You have If debris were to get caught in the water injector, the engine would not run lean as the injector is not responsible for delivering any of the engines required fuel supply, it only delivers atomized water to cool the charge air. The air/fuel ratio would remain identical to what it previously was and any resulting detonation would be due to the hotter charge air rather than an improper a/f ratio.

Good point, but A) Just about all water/alky injection systems out there include "Clogged nozzle LEDs" to let you know when the water is not being sprayed through the nozzle. Also, it's your duty as the owner of your car to do regular maintenance/checkups on your car. This is just another small thing to add to the list. If you set up your WI system properly, then no debris should even get near the nozzles, much less get in the system anywhere else. The only real way a nozzle could get clogged is if you happen to pick up a couple bad/contaminated gallons of distilled water. And honestly, I would be much more worried about quite a few other things failing on the car in the middle of a run. A slightly clogged water-injection nozzle would be near the end of my list of things to worry about I'd much rather have the WI nozzle clog than a fuel injector clog You get the idea.

[nissanfanatic]

Nah, I wouldn't deny the positives. I'm just saying I don't like it.

[Hypsi87]

I am not a fan of pure water injection but Alcohol injection is the way to go...

All water does is steam, it does not burn. Alcohol in the other hand has HP potential.

As far as upgrading an intercooler over alcohol injection... What intercooler do you konw of that you can run alot of timing and boost on 93 octane pump gas for under 500 bucks???

when I am not spraying alcohol I can only run about 19* of timing and 15 PSI of boost on stock heads and intercooler. With the alcohol injection, I am up to 24 degrees of timing and 25-26 lbs of boost.

Don't knock it untill you try it. Not only is Alcohol a naturall anti deatonate, it is a fuel.

Here is a very good FAQ about alcohol injection...

It is not a band-aid to cover up a problem. The problem is Pre deationation, and alcohol injection gets rid of it. it offers a great alternitive to buying 7-11 dollar a gallon race fuels to run the higher boost levels that we all want on the street.

[Hypsi87]

Originally Posted by guitarXgeek

There's a reason that the old turbo buick guys ran it back in the day, and it sure as hell wasn't as a "bandaid" I can garauntee that ANY properly setup and tuned turbocharged motor will see dramatic gains from a water/alcohol injection system (assuming an air-to-air intercooler is used. the benefits are arguable on setups using water-to-air coolers).

I resent that OLD TURBO BUICK GUYS remark... Accually the turbo Buick guys have just recently goten into it in the past 4-5 years.

Personally I hope people don't catch on to alcohol injection and us Buick guys keep the advantage

[Sluttypatton]

Originally Posted by Hypsi87

when I am not spraying alcohol I can only run about 19* of timing and 15 PSI of boost on stock heads and intercooler. With the alcohol injection, I am up to 24 degrees of timing and 25-26 lbs of boost.

That would be one of the times where I think water or alcohol injection is a great idea. What I mean by a "band aid" is someone running relatively low boost and still needing water injection to avoid detonation.

[Hypsi87]

Originally Posted by Sluttypatton

That would be one of the times where I think water or alcohol injection is a great idea. What I mean by a "band aid" is someone running relatively low boost and still needing water injection to avoid detonation.

ok yea I agree with you. you need the boost to support the injection

[Zgringo]

Mr. Hypsi87, Shudup, don't be telling these guys our secret. Let'em keep retarding there timing and running lower boost's so it don't make max power and can run on regular pump gas. And don't tell the guys that run spray that with W/A injection they don't have to retard the timing as much and have lessend the chance for a piston meltdown, due to hi-heat.
And for sure don't tell'em after a run with Alky spray you have frost on your intake manifold.
Keep'em in the dark and don't tell them that it's being used in all sorts of racing by top tuners.
And please don't tell them to call Kevin at Majestic Turbos (800-231-5566), one of the top turbo men and ask him why he runs alky injection in his engine.
Lets you and me an a few select keep our a secret.

[guitarXgeek]

Originally Posted by Hypsi87

I resent that OLD TURBO BUICK GUYS remark... Accually the turbo Buick guys have just recently goten into it in the past 4-5 years.

Personally I hope people don't catch on to alcohol injection and us Buick guys keep the advantage

My bad, what I meant to say was those MODERATELY AGED TURBO BUICK GUYS I'm glad you guys see the tremendous benefits of water/alky injection. I don't get the whole "band-aid" idea, in my book it just doesn't hold water (pun intended ).

[Zgringo]

Ab Jakins in the Marmon Meteor in 1937 set a world record and was using water/alky injection. Then Germans and the USAF were using it also in 1939-????. I might also add they were using Nitrous.
Water/alky has been around alot longer than most of your Grandpa's. I learned it's use in the 40's from my mentor and friend Lou Meyer winner of the Indy 500 3 times.
As for being a band-aid, if anything is a band-aid the intercooler is. The IC was designed for lazy people, the ones who never checked there windshield washer fluid level.
We use to run over 5 bar (70#) boost to qualify, and 3.5 bar (50#) to race before IC were even invented. Try that with your IC equipped cars.
A fact is the IC has a 1.5-4 lb. loss in turbo outlet pressure. In other words it restricts the flow of air in the system.
Isn't it amazing we spend so much on free flowing heads, cams to enhanse our intake and exhaust flow, exotic exhaust systems to aid in removel of spent exhaust and hi-end turbo's only to install a IC that drops the turbo pressure 1.5-4 lbs.
What's really amazing is something that doesn't cause any loss in turbo pressure, and is proven to have more temp. droping ability than a IC, plus keeps the combustion chamber super clean, major temp. reducing abilities and lower EGT, and is called a band-aid for a improperly setup car. Even N/A engine benefit from chemical injection, as do low output turbo cars.
Hypsi, my hat's off to you for taking old technology and applying it to modern engineering. It's people like you that become winners and not the ones that poke fun because of there ignorance.
All of us (including me) are ignorance till we learn and are taught. If I can't pass on what I've learned to those wanting to learn, then I've failed and all my past is a waste.