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Discussion Starter #1
Anyone big on electrical wiring? I'm decent at it and I think I can figure this out anyway, but would anyone have any good plans for adding an auto feature to the IC spray?

It should be as easy as adding a thermocouple to the IC and then a transistor of some sort to turn the spray on until the temp lowers below the set point.

Off to radio shack!
 

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Cool, I've been thinking about the same thing. I too am no wiring genius but would somehow figure it out. Another issue is placement. Too high and it might never get hot enough, too low and it will be hot all the time.
 

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I would put in some more logic than just what a thermocouple can provide. Maybe the addition of a timer would be good, so that if it is too hot outside, and you can't lower the temp to the set point, it won't drain your resevoir. You could also put in a float switch into the resevoir (or tie into the factory "low fluid indicator") so that you don't attempt to pump if there is no more fluid. You should be able to throw together a small computer to handle the logic -- maybe something based on a HC6811 (I think that's what that all-in-one thing was called). What does it take to tie into the ECU for something like this? I've seen the devices to go from the OBD2 connector to RS232, but there may be a less expensive way.

The more I think about it, the more complicated it seems. If you do come up with something good, start selling them. There should be a good market for it. <Pip>I'd pay one hundred dollars for one!</Pip>
 

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Discussion Starter #4
I've got a design made up here that I think will work. Using diodes, an op amp, a few pots and a regulator.....

I'll have to get the pieces together and try it out....might have something worth packaging and selling here.
 

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Well I was just thinking about it. So you are much further along than I. If you make it first I'll be sure to pick one up. :D
 

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Has everyone seen this?

http://www.autospeed.com/cms/article.html?&A=0527&P=1

It is a nice discussion of how these guys played around with different ideas for when to turn it on/off, and how they went about it. Some stuff on the sprayer and so on as well, but of course we already get that from the factory. After explaining their idea, they even sell the module for US $63, or boxed with thermistors for $132. Given that I'm a software guy rather than hardware, this sounds perfect. I just need to convince one of the local Subaru guys that this is so much fun that he would want to help me install it. :)
 

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Hail to the engineers... you are much smarter than I.

My motto is:

Why use something ready-made when you can do-it-yourself?

That way you get the full experience... :)
 

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Discussion Starter #8
Hmmm....that article is certainly interesting, but it seems to leave one thing out......

The driver will know when he is going for a hard drive while there is no way in hell that controller will.

It may see that you are driving hard after it's over, but wouldn't you actually know before it would?

The design I have here would compare the ambient temp to the IC core temp. Of course you'll still have manual control (ON/OFF) but this will add an auto mode you can turn on. You can activate it when you know you'll need it, and then it'll watch the IC core temp and cool as needed.

We'll see how it works.....parts are on the way!
 

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Discussion Starter #10
Well, prototype complete and working well. I think it would be pretty easy to make two versions of this.

One would use one temp sensor. Depending on the weather, you could set the temp you would like the spray to turn on. Of course this is needed because while a 100 degree IC isn't bad in the middle of the summer, that's really bad in the winter. You need a way to tell the sensor how hot is hot.

The second version can use two sensors to determine the ambient temp and then you would set the difference. For instance, if you want the spray to come on when the IC is 30 degrees higher than ambient, you'd make that adjustment and then it will take care of the rest, regardless of outside temp. 30 out, spray at 60. 100 out, spray at 130.

Here's a few pics. Not pretty, but I need to get a real board made now that I know it works.

Here is the two sensor model. At this point, IC and ambient are the same temps, so the spray is off (light off).



And here, when I apply heat to the IC sensor, the spray comes on (light on)



I'll let everyone know when I get a 'pretty' version together and of course if it really works on a turbo w/ IC car.
[/img]
 

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Your idea with 2 sensors is very good, one thing on it spraying, how long will it spray? you don’t want the spray to stay on still the temp goes down because ull just drain the reservoir. which i think someone else mentioned. can you make it spray in a few second intervals? :-?
 

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Discussion Starter #14
It work as if you are sitting there holding the button until the temp diff is cleared. This means it will be a 2 second spray, followed by a 2 second delay and so on.

As for draining the reservior, that's really up to you. If you set the temp diff too small, yes you will. If you set it too high, you won't. If you adjust it for a daily driver setting and a race day setting, you should use be able to use water at whatever rate you like.

You just have to ask yourself this.....do I want that power advantage without thinking about it? Daily driving...probably not necessary. Autox day.....leave it on and worry about other things between heats.
 

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hello everyone i am new to this forum and i just want to say this I/C spray topic is great, and is the actual working model done yet?? :D
 

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Discussion Starter #16
It works fine. It hasn't been tested on an IC equipped car yet. With my recent hospitilization, things have slowed down.

We'll see how it works once the car gets here.....
 

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Discussion Starter #18
I see a few problems with that system from just an engineering standpoint. As the article that was linked early stated, an IC works as a heat sink. It absorbs heat and it doesn't do so immediately. If you run really hard and stop to feel the IC, it probably won't be too warm. The heat has to have a chance to raise the temp of the rather large fin area.

I don't see why you'd trigger on boost. This system I'm throwing together will watch nothing but the IC temp. When it's hot....cool it off. Why is that so hard?
 

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bump. any status on the auto-spray system?? I am interested.
 

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Discussion Starter #20
It's still sitting in a box at my place. My STi will be here any time now and I'd love to give it the real world test before doing any more development. Unfortunately, I have a wedding in 2 weeks, a week long honeymoon and another back surgery to deal with in the near future, so a final product is probably at least a month away.

But thanks for the renewed interest.
 
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