Intercooler water spraying system
 

Hi all,

I'm wondering if anyone have water spraying system on their intercooler? is it a good idea to do? I searched, and found a few threads but they are old and all direct to injection system instead.

I don't want to do injection system because I will have to get my FD tuned again. Not to say the complication of getting the injection system working right.

a spraying system like STi sounds simple and cheap yet get temperature down up to 35%.

any ideas? please share.

thanks

My friend used his windshield wiper bottle and motor to direct water spray to IC/Oil coolers. He didn't use it for windshield anymore since getting CF hood.

I havent picked up my fd yet but when I had a pretty quick dsm I used a co2 I/C sprayer, granted I only used it once and never got it filled again :P I found that meth injection was the way to go for that car at least. (dsmlink and a wideband made tuning easy plus the fact that there arent any awd dynos around here left me no choice) Doubt this helps you any but the co2 "kits" are fairly easy to make yourself. Also Ive heard of I believe the sti guys pumping washer fluid WITH the co2

are you talking about CryO2 system? how much per refill per tank? yeah that would be an awesome system to have but I don't see any FD owners with one.

That is a sweet idea, nice!

cheap and simple with tees and nozzle end from your home depot. I have to admit I can't see how its too practical...really...when would you spray? Can't use it at the drag strip cause they'll pull you out if they see you dripping any fluids, can't see using it on the street as it wouldn't cool fast enough for a light to light drag, probably best if you were trying to keep IC cool between stages...but then I'd use a bag of ice.

I was thinking autocross

I've never had to get out of 2nd gear in any autocrosses I've been too (maybe that's why I'm no longer much of a fan)...and the seat time isn't so long that I need to cool the engine too much...usually you get a quick run then sit...then quick run. autocross isn't usually a high hp event needed to win kind of situation..more driver skill, car set up IMO. I"ve seen really good drivers get best times beating vettes and vipers all day.
For this stuff I think you'd be better off saving for PS or Oil coolers vs worrying about keeping IC cool.

for that matter...tires will make you faster.

Correct but I had a friend that did it before they became popular - he had his own business and they were fairly simple to make. Not sure on the fillup but any fish store or paintball shop would be where you need to take it. In all honesty like I said above I found a lot more benefit with the meth injection - higher octane/boost, lower intake temps, more cost effective

I believe STI's have this sort of setup stock.

It doesn't drip like you'd think, almost all the liquid flashes to vapor as soon as it hits the IC.

How did he get the windshield wipers not to start wiping as soon as he pulled the sprayers?

The water should spray a mist of water and yea it should evaporate when it hits the IC. It isn't just spraying water on it. You have to remember what happens when you spray at speed as well. I'm sure it might help but I kind of doubt the 35% claims. I dunno.

Honestly, I think you should go AI. Getting the car retuned isn't that big of a deal dawg. I love my aquamist kit + rx7 summer man. I couldn't imagine driving without it now. It is worth the complexity.

rewired

Many years ago, one of the members here tried one of the kits like the NX N tercooler Kit. He ended up blowing his engine, but I don't think he ever determined it was directly related to the kit. I've seen a few owners (not on this forum) with the NX N tercooler kit installed on FMIC's, but never actually see them use it. I think it's more of a novelty thing.

I rigged up a bag and pump combo out of a semi truck (it's about a 1qt bag) to a boost switch set at 4psi.

I didn't have an undertray at the time but I could still watch my IATs drop pulling on to the highway. I haven't run it since the beginning of last summer. IMHO it got decent results for the $50 or so I had invested.

You mean so you can be like.... hey check out my sweet nos, just like fast and furious!:lol:

Both the Evo and STi have an intercooler spraying system from the factory. The STi has a top mount intercooler and the sprayer is integrated into the scoop area. It is manually controlled by a push button. The Evo has a factory front mount intercooler and the sprayer is controlled by the ECU although it can be turned off. The water vaporizes usually vaporizes very fast.

I've got some diagrams of these systems at home, I'll see if I can post them later.

Autospeed has a good article a few years back on it -

http://www.autospeed.com/cms/A_2719/article.html

They have some related projects, like a controller for it and stuff.

IMHO, it's better injecting into the motor. You don't necessarily have to tune for it, a "mild" AI setup will just provide more cooling and drop your intake temps. Might be worth doing some research on that point (I'm not speaking from first hand experience) but directly cooling the charge seems more logical to me than cooling the intercooler.

Dale

Even if it did work unless it dropped it way down it would hardly be worth it. I just cant see the power gains being worth the hassle. I have a hard enough time remembering to kill the AC before bouncing off the rev limiter.

There are just too many way to make the power gains in sustainable passive way.

Here's the sprayer on an Evo VII:

https://www.rx7club.com/attachment.p...1&d=1301019681

You can see that the switch is near the parking brake while the reservoir is in the engine bay near the factory FMIC. The STi has the sprayer on top of the intercooler where the hood scoop can flow cool air directly over it. If you ever see an STi operate its intercooler sprayer you might see steam coming out of the hood scoop. The reservoir is in the trunk on the side, while the switch is to the left of the steering wheel.

https://www.rx7club.com/attachment.p...1&d=1301019681

I've never measured intake temp changes on either application. Neither the Evo nor the STi have an air temperature sensor located after the intercooler. The IAT is integrated into the airflow sensor which is before the turbo. So you would have to go through the trouble of installing an extra IAT sensor and logging it.

The STi only operates the sprayer manually by a switch, but here's some information on the way Evos automatically control the sprayer.

https://www.rx7club.com/attachment.p...1&d=1301020805

You have a set of minimum conditions such as air temp (measured at the airflow sensor), water temp, engine load (calculated from the airflow sensor signal), and throttle position. Then you have a max speed above which the sprayer will not operate. And then you have a cycle time for the ECU to engage the sprayer relay, where a higher ON time would correspond to more spraying.

It would be cool if Mitsu had an air temperature sensor right after the intercooler like Ford and VW use on some of their turbo engines, but that would have made the system more complicated and expensive.

I'm not sure why it has to be complicated, you're spraying water on the outside of the intercooler. There's no tuning involved, and you can up the tank with a hose.

Now if you're going to go high pressure like one of the versions in autospeed and actually have a mist spray then I suppose there could be some benefit to a controller since you're already spending a decent bit of money...however at that point you should probably be considering actually ingesting that mist.

For the most part its used for back to back runs to prevent heatsoak. Ive used both on my dsm, with the injection part (go to home depot get a gallon *possibly two i cant recall as its been years* of methane and mix 2 cups of distilled water for an 80/20 mix.. dont use just windshield wiper fluid or its a waste) I was able to run 30 lbs of boost on a dsm with a fp red turbo... 0 counts of knock. Injection would definately help more, but if your sitting in 100+ temps at your local drag and are the only one there doing back to back passes or just want to eek out every possible hp from your setup then build an ic kit for cheap ( i wouldnt buy one) and toss your heat soak concerns out of the window.

+1

Save the time & money on a "sprayer" and go with water injection. It is a whole new world.