Intercooler water spray

boostjunkie · Post by **boostjunkie** » Thu Jun 12, 2003 7:22 pm

Since I had the engine all apart these part couple of days I decided to wire in my intercooler water spray. Here's what I had for parts:
1. 2-pump legacy station wagon water tank
2. sti spray nozzles
3. buncha wire
4. push-button switch
5. hose, t-fitting
6. zip ties

I wasn't able to do a really good install for the sprayers, so I just zip tied them to the intercooler. Until I get some l-brackets, the sprayers only wet the inlet side of the intercooler core from the turbo. Has anyone with a spray system been able to cover their whole core with water? How did you mount your sprayers?

rsstiboy · Post by **rsstiboy** » Thu Jun 12, 2003 10:40 pm

I have seen guys over here with wrxs mount the sprayers inside the bonnet scoop along its opening (about 4 garden sprayers)

eastbaysubaru · Post by **eastbaysubaru** » Fri Jun 13, 2003 12:59 am

Yup, all of the intercooler sprayers I've seen, including the factory ones, mount to the inside of the hood scoop. They're routed like the windshield washers. I'm not sure how many actual nozzles there are, IIRC it's two but I could be wrong. Additionally, I've heard/read that the garden type misters don't creat a fine enough mist to be nearly as effective as the actual Subaru nozzles.

-Brian

boostjunkie · Post by **boostjunkie** » Fri Jun 13, 2003 12:53 pm

The only problem with that setup is that my v2 core is SLANTED. Some of the water spray will be lost because of the hoodscoop being misaligned with the core.

eastbaysubaru · Post by **eastbaysubaru** » Fri Jun 13, 2003 4:13 pm

Gotcha. Yeah, that makes it a little tougher. I'm not sure what you'd want to do in that case.

-Brian

Redline Dreamz · Post by **Redline Dreamz** » Mon Jun 30, 2003 2:51 am

spray alcohol, evaporates more quickly

LegacyT · Post by **LegacyT** » Mon Jun 30, 2003 3:07 am

So your spraying onto the external suface of the intercooler? I Always thought they spray into the intercooler and the engine sucks in the water (or more precisely humid air/fuel mixture). Add alcohol and you have more power as well.

Mark,

91White-T · Post by **91White-T** » Mon Jun 30, 2003 3:46 am

LegacyT wrote:engine sucks in the water

Not at all, in fact that would be really bad

subiekid · Post by **subiekid** » Mon Jun 30, 2003 6:05 am

maybe you are thinking of water injection

LegacyT · Post by **LegacyT** » Mon Jun 30, 2003 1:40 pm

The engine sucks in humified airfuel mixture to cool it down, I guess that's water injection. Ok so this is a whole different realm of intake charge cooling. My wrong sorry,

subiekid · Post by **subiekid** » Mon Jun 30, 2003 5:34 pm

dont worry about it, that is why we have this board, its to learn.

Redline Dreamz · Post by **Redline Dreamz** » Tue Jul 01, 2003 10:50 am

subiekid wrote:dont worry about it, that is why we have this board, its to learn.

But you learn wrong if you read stuff like this --

"The engine sucks in humified airfuel mixture to cool it down, I guess that's water injection."

The only thing right in this sentence is the word "cool". Water injection doesnt even use water, it uses a deluted mixture of alcohol and water or alcohol and nitromethane i.e. windshield washer fluid/Windex or a model airplane fuel with a low oil content. Secondly there is no "humidifed air/fuel mixture" on a FUEL INJECTED CAR. Unless were talking about a TBI or a carburated engine, this is not the correct phrase to use to teach someone basic engine theory.
A water injection setup is used to cool the cylinder temps when you have an extremely high static compression ratio. Static compression is your base piston compression plus any additional from power adders i.e. turbo(s) superchargers and or nitrous oxide. This helps cars running 13:1 static compression stay on 93/94 pumpgas under normal driving but can be aided at will with the use of the injection system. It works similar to a nitrous oxide system. A silinoid is hooked to a source and the intake pipe. When the TPS (throttle position sensor) reads 80% throttle or above, the silinoid injects the liquid therfore cooling your cylinders so you can remain on pumpgas. It carries many differnt uses but that is the most common... high compression NA engines wanting to stay on pump fuel.

LegacyT · Post by **LegacyT** » Tue Jul 01, 2003 1:01 pm

Dude,

I thought this thread was bout water injection then found its just intercooler spraying. I was just trying to be general in my wording. Water injection system does increase the humidy of the intake charges air part , the other part being the amount of fuel present. It actually reaches 95 - 100 % relative humidity, and it works by latent heat of evaporation, where heat energy is passed from the air to the water because the change of state from liquid water (spray mist) to vapour (humid air) requires energy and thus taking it form the air lowers its amount of heat energy, therefore cooling the air in the process, which is what we want. This leads to lower intake temps, lower chances of detonation and cooler EGT's which indicate like you said lower cyl temps. Water injection is like a fuel injector squirting a fine mist of water into the intake charge. You just talked about the technical hooks up to install a water injection system, but didnt get into the theory of how it actually works, yet still stated that I was wrong.

IggDawg · Post by **IggDawg** » Wed Jul 02, 2003 2:28 am

Redline - Chill, man. LegacyT knows what he's talking about most of the time. it's a common misconception to mistake an the term "water spray" for "water injection." an "intercooler water spray" would be misconstrued for a water injection system with the point of induction being at the IC.

anyone will be able to read down and see that he was corrected. nobody will finish this thread and still mistake the 2 terms. so lets not get all up in arms. this is a friendly place.

Anyways, I'd like to point out something very important that LegacyT said that applies water spray kits. the amount of energy that water absorbs when changing phase from a liquid to a gas is several times more than the amount of energy it would normally absorb through standard heat conduction. this means it's much better to use washer fluid in your water spray than just water. there is a certain amount of alchohol in the mixture that will evaporate quickly, absorbing more heat than it could normally absorb in its liquid form. if you have a heat soaked engine bay, and your water tank is at the same temperature as your IC and your ambient engine bay temp, you can still get benefits from a water spray by allowing the evaporating liquid to absorb heat from both the IC AND the air passing over the IC. we have very little airflow for TMICs to use, so every little bit helps.

Redline Dreamz · Post by **Redline Dreamz** » Wed Jul 02, 2003 7:15 am

LegacyT wrote:Dude,

I thought this thread was bout water injection then found its just intercooler spraying. I was just trying to be general in my wording. Water injection system does increase the humidy of the intake charges air part , the other part being the amount of fuel present. It actually reaches 95 - 100 % relative humidity, and it works by latent heat of evaporation, where heat energy is passed from the air to the water because the change of state from liquid water (spray mist) to vapour (humid air) requires energy and thus taking it form the air lowers its amount of heat energy, therefore cooling the air in the process, which is what we want. This leads to lower intake temps, lower chances of detonation and cooler EGT's which indicate like you said lower cyl temps. Water injection is like a fuel injector squirting a fine mist of water into the intake charge. You just talked about the technical hooks up to install a water injection system, but didnt get into the theory of how it actually works, yet still stated that I was wrong.

This is exactly my point, the information your giving is secondary theory, not basic facts --

and it works by latent heat of evaporation, where heat energy is passed from the air to the water because the change of state from liquid water (spray mist) to vapour (humid air) requires energy and thus taking it form the air lowers its amount of heat energy, therefore cooling the air in the process, which is what we want.

This process is a theoretical byproduct... not the reason for using the injection system.

This leads to lower intake temps, lower chances of detonation and cooler EGT's which indicate like you said lower cyl temps.

True but again... a theoretical byproduct... not the reason for using it.

Water injection is like a fuel injector squirting a fine mist of water into the intake charge.

does this look familar??? It works similar to a nitrous oxide system. A silinoid is hooked to a source and the intake pipe. When the TPS (throttle position sensor) reads 80% throttle or above, the silinoid injects the liquid therfore cooling your cylinders so you can remain on pumpgas.

Now if youd like me to get all into the REAL reason as to why it works id be more than happy to.

Injecting water and alcohol is made to cool the CYLINDER WALLS during the combustion cycle. The atomized water/alcohol mix breaks down durning combustion. The water breaks down to hydrogen and oxygen and the alcohol binds with the left over oxygen. The 2 Hydrogen atoms are what do the cooling, in a similar fashion that nitrogen in nitrous oxide does, just not nearly as effective. The alcohol alone is a combustable, but when bonded with the extra oxygen atom it becomes a lubracant, but still burns. Injecting water alone will cause a SEVERE LEAN STATE which can and will break and/or burn holes in things. Using a alcohol/nitromethan mix cools and lubracates even better than the water alcohol mix however it is less than cost effctive being that a 1 gallon jug of alcohol/nitromethan/oil (40%/40%/20%) is about $20 bucks and change. Injecting Nitrogen alone is the same idea as injecting strait oxygen.... ALL SORTS OF LEAN. There is testing of using CO2 in hopes of the carbon atom becoming a super lubracant but is not proven to work yet.

Thats just a summary of how the injection system works and why you use it the way you do.

IggDawg · Post by **IggDawg** » Wed Jul 02, 2003 7:46 pm

the reason running lean is bad is that combustion temps soar. this causes high cylinder temps, and in turn can cause pre-ignition knock due to hot surfaces. injecting water and alchohol into the mixture WILL reduce combustion temperatures as teh water will absorb a lot of energy while turning to steam. alchohol will absorb even more as it is more volitile. This is one of the PRIME reasons for water injection. your lubrication explaination may have something to do with it, but don't doubt that lower combustion temps are the main reason for water injection.

and it's a "solenoid" not a "silinoid." solenoids are coils of wire, and silinoids are aliens. big difference. I have no aliens in my engine.

-IggDawg

Post by **Legacy777** » Wed Jul 02, 2003 8:47 pm

IggDawg wrote:the reason running lean is bad is that combustion temps soar. this causes high cylinder temps,

Just want to add something to this. Running lean will not ALWAYS cause temps to go up. It all depends on where you are along the parabolic burning curve. If you are at stochiometric, and lean the mixture, MEP, peak firing pressures & temperatures will decrease.

If you are on the rich side of the curve, and lean, yes you will increase MEP, peak firing pressures and temperatures

I think this is one of the big issues when people tune, they don't know where started from along the curve, so it's sort of a guessing game, and if you guess wrong....engine goes BOOM!

Redline Dreamz · Post by **Redline Dreamz** » Fri Jul 04, 2003 7:46 pm

i was all excited when i saw this cuz i thought someone actully knew what they were talking about...

the reason running lean is bad is that combustion temps soar. this causes high cylinder temps, and in turn can cause pre-ignition knock due to hot surfaces.

but then you had to go and fuck it all up by saying this...

injecting water and alchohol into the mixture WILL reduce combustion temperatures as teh water will absorb a lot of energy while turning to steam. alchohol will absorb even more as it is more volitile. This is one of the PRIME reasons for water injection.

And then my eyes lit up when i saw this...

Running lean will not ALWAYS cause temps to go up. It all depends on where you are along the parabolic burning curve.

but then...

If you are at stochiometric, and lean the mixture, MEP, peak firing pressures & temperatures will decrease.

If you are on the rich side of the curve, and lean, yes you will increase MEP, peak firing pressures and temperatures

but you saved yourself with...

I think this is one of the big issues when people tune, they don't know where started from along the curve, so it's sort of a guessing game, and if you guess wrong....engine goes BOOM!

Between the lot of you guys seem to be able to piece together whats really going on here so ill leave it alone call it quits.

vrg3 · Post by **vrg3** » Fri Jul 04, 2003 9:00 pm

Redline Dreamz, I have to say I don't think you're being very helpful. None of us knows everything, and we're all trying to add our little bits of knowledge to the communal pot.

Whenever anyone posts anything, a reply can help if it contains confirmation, corrections, or additional information. It's even better if it includes some better reasoning or qualification.

And please don't curse unnecessarily.

Post by **Legacy777** » Sat Jul 05, 2003 2:13 am

Redline,

Rather then just saying I'm wrong, why don't you explain it huh?

I can scan a document from a course I just took that backs everything I said.

Redline Dreamz · Post by **Redline Dreamz** » Sat Jul 05, 2003 7:12 am

Legacy777 wrote:Redline,

Rather then just saying I'm wrong, why don't you explain it huh?

I can scan a document from a course I just took that backs everything I said.

But your information was semi correct. All the things you said happen, do... the things you were incorrect on were 1, the original reasoning for using the system and 2, you were attempting to teach somone something new, but didnt know the system yourself. Thats like me teaching a class in African Basket Weaving. Im sure i could read a National Geographic artical and make the rest up but unless you are 150% sure as to the theory your teaching... its probably not a good idea to teach it. This is how the infamous "rice kid" starts. Like the word WOOT... someone said you say it becuz thats the sound you cold air intake makes but in reality someone simply mispelled WOT (wide open throttle). Thus you have one stupid kid spreading misinformation and stupidity across the board.
This is why when i try to learn new things, i look to the Iron Men, the guys who have 25yrs in and are running 8 flat in that same 72 Malibu they got when they were 20yrs old, and drive that fine piece of American muscle home from the track.
Sure Kenny Tran, Lisa Kubo, and Saad Saad know what theyre doing, boy do they, but ill lean toward Big Daddy, Doug Rippie and John Lingenfelter anyday of the weak.
Did someone in the hotrod class use an alcohol injection to cool intake temps, quite possibly. However you go call up Gavin Ortan and ask why his 1200hp blown 540ci has over 100, 7 second passes under its belt and he'll tell you otherwise

vrg3 · Post by **vrg3** » Sat Jul 05, 2003 3:23 pm

We don't always have the luxury of having an expert on hand.

There's nothing wrong with students sharing their information with each other.

It's also worth noting that the automotive world is fraught with accepted reasoning and "facts" held true even by experts which turn out not to be true. Nothing's exempt from being discussed and analyzed again by a newcomer.

Grant · Post by **Grant** » Sun Jul 06, 2003 2:42 pm

So are you implying that Gavin has 100 7 sec. passes because he does not have alcohol injection. That sounds kinda fishy to me. I think you need to quit reading so many NHRA, Turbo, Sport Compact Car, etc. and stop trying to show off. This forum is a group of people who I consider to all be friends. Everyone puts their collective knowledge together for a free education. There are people on here, like Mile-Hi Al who have been tuning Subaru's since before you were probably born. There are others, like Adam from Z1 Performance, and Nate from S-squared that are from respectable Subaru tuning shops. Seldomly do I notice anyone being rude or insulting to each other. But recently I have been noticing your posts seem to be somewhat rude and condescending. I would appreciate it if when you decide to spout off about something, do it in an informative manner not in a WWE I'm gonna show these guys kind of an attitude. Thank You.
Oh yeah, do you have a Subaru?

Post by **Legacy777** » Mon Jul 07, 2003 2:27 pm

What I posted is correct!

You took snippets from my post as well as other posts and put them together. I said nothing about alcohol injection in my post.

Before you say someone is incorrect, I suggest you take a little closer look at who posted what!

I will not tolerate being told I'm wrong when I have the knowledge and supporting documentation, which I've double double checked in case my memory has lapsed.

This is the end of this discusion, and I will not tolerate you or anyone else disrespecting myself or any other member. If someone has posted incorrect information, by all means correct them, but do it in a constructive and polite manner, or don't do it at all!

evolutionmovement · Post by **evolutionmovement** » Mon Jul 07, 2003 11:17 pm

Non-constructive criticism just shows true ignorance. There's a reason I come to this site instead of I-Club. Just like the Legacy is a little higher quality than the Impreza, I like to think the owners' club is too. I could go on about my vast knowledge of auto history that I'm sure others may not know in a belittling manner, but what's the point? As if it makes me anything more than a bigger dork to know what the final drive was on a Iso Grifo 327 or some such irrellevant info my head has collected. No matter how much you know about a subject, there's always someone who knows more and there's no way you'll learn by attacking others. I hope this all makes sense as I'm just spouting off - only removing the swears.

There are far more ballsy ways of starting fights than in an internet forum.

Steve.

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Intercooler water spray

Intercooler water spray