Hi All,

I have a 2006 STI with the I/C water spray.
My question is, does it actually improve anything when using the car in the UK, anyone seen a difference using it?

 

Yes it works better if you have auto ic, my old spec c used an entire 12ltr tank on a hot day in 200 miles!

Tony

 

I just leave mine on automatic and forget about it

 

lol 2005 STI are only manual?

 

you'll be saying you don't have a rear wiper next

 

lol nope, it must have fell off lol
Are the jap imports automatic then?

 

lol they mean automatic intercooler spray
it automatically sprays onto the intercooler when you boot it

 

lol thats what I ment, do the imports only have the auto spray when booting it?

 

oh sry mate yes they do have the auto spray

 

bugger lol, never noticed any difference using mine though, what difference do you normaly see when using it?

 

We have 2 buttons. One of them switches it to automatic and the other button is a manual spray. Quite how you are supposed to reach down and press it when giving it death I don't know

As to whether it makes a difference I guess it's one of those things that works well in theory but in practice probably makes very little difference.

On a boiling hot day I assume it would make more of a difference

 

Its like the DCCD-A. I tend to just leave it auto mode. Figure the computer is going to realise which wheel needs traction quicker than I can.

 

Makes you think, if the bottle is in the but and the car is in the sun, the water wont be cold so can not see what real difference it makes, seems like bit of a gimic i think.
Water spray used to be fine mist in the intake which did improve power etc, not water sprayed on to a coller.

 

It reduces the temperature of the intercooler and hence the air charge temperature - so yes they do work - a little!

 

Here is the science bit :-
Evaporative water cooling is based on a physical phenomenon in which evaporation of water into surrounding air cools an object or a liquid in contact with it. As the liquid turns to a gas, the phase change absorbs heat. Technically, this is called the “latent heat of evaporation”. Water is an excellent coolant because it is plentiful, non-toxic, and evaporates easily in most climates. Six gallons (22.7 L) of water evaporating has the same cooling effect as a typical (3.5 ton-hour) home central air-conditioner.

The most common example we all experience is perspiration, or sweat, which the body secretes in order to cool itself. The thin layer of water evaporates; the water vapor absorbs heat as it evaporates off our skin. The amount of heat transfer depends on the evaporation rate, which in turn depends on the humidity of the air and its temperature. When the air humidity is very high, sweat evaporates slowly. This is why you feel hotter in humid climates compared to dry climates of the same temperature: the sweat cannot evaporate as fast to cool your body in a humid climate.

So if it works to keep us cool then this should work :-

Water sprays on intercooler fins.

Water evaporates.

Temperature of fins is reduced.

Temperature of air inside intercooler is reduced.

Engine makes more power from cooler air.

Water injection is entirely different as it's sprayed in with the fuel/air mix where the initial injection of water cools the fuel-air mixture significantly, which increases its density and hence the amount of mixture that enters the cylinder. An additional effect comes later during combustion when the water absorbs large amounts of heat as it vaporizes, reducing peak temperature, and reducing the amount of heat energy absorbed into the cylinder walls.

 

and that's why I leave it on auto.

 

Wise move.

 

I think the the intercooler should have some sort of heat shild around it. Or maybe some sort of jacket to help protect from engine heat. I also think the intercooler should have
2x big fans on it to help coolling cycle. Just an idea !
Check this out http://dvdtfab.com/intercoolertestlab.pdf

 

But the question still remains, has anyone noticed any difference using it lol

 

None!

 

Is it possible to change the manual spray to an automatic on a UK car?

Is so, how?

 

splash your face with cold water and run into the wind and see how cold your face gets!

 

I believe it's linked to the ECU.

 

The guys that do 1/4 mile runs are probably the best to answer that. They are known for giving the IC a squirt before launching. I believe some even use a alcohol/water mix to improve charge cooling.

For everyday road use you probably won't feel the difference. It will lower temperatures quicker from heat soak after sitting in traffic & help protect your engine on boost until it's reached ambient levels again.

It's a well known fact turbos don't like hot air. Go for a blat on a cold misty morning & you should feel the difference to the same run on a hot dry day. The principle is the same ,whether you notice the difference or not is down to you.

 

Some regular Lancia Integrale Evo 1's were manufactured with I/C water spray equipment in order to homologate that particular gizmo for Group A rallying back in about 1991. Lancia didn't even bother plumbing it in so you had to get your dealer to do it (or yourself). In normal use it is generally considered by Integrale owners as having negligible effect on the road-car's performance, but may have been worth the odd extra bit of oomph in the works rally cars.

 

on a really hot day it will make a difference and has already been said it will reduce the likelehood of knock which allows you to keep boost wound up.

 

If I could see the wiring diagrams for the Jap cars, I could so out if its easy to make automatic, an ideas where they can be found?

 

I think they're more popular in hotter countries-down-under etc

 

If I can find a wiring diagrams for STI with them as automatic, I can see if a retro fit is easy.

 

Got it on my 03 STI PPP and the most significant thing I would say is when I use it if the radio is low then I hear a little interference through the speakers... apart from that absolutley no difference.