Charge cooling with water

**Evodelta** · 04-10-08, 19:00

Air to water cooling.

Or chargecooling as it is known as in the UK, a bad descriptive term I think and don't agree with it.

The basics:

The hot charge air goes through the cooler matrix just like in an air - air unit, except on the other side of it is water circulating instead of cooling air.

Why?

This system is used where you have no space for a decent sized air - air unit, OR you have no good flow of air near the motor like in a rear or mid engined car.
Or, you have a boat with a turbo engine, boats/ships usually travel slowly so there is not much high pressure cool air, there is however a never ending supply of cold water to be used, here a near 100% efficiency can be had.

What kind of car?

Not a circuit car, it favours drag cars, hill climbers and road cars.
This is because they all have short bursts of boost with off boost periods afterwards where the water can be cooled down. If it was used on a circuit racer then the water would get hotter and hotter the further you drove (or you would have to fit a HUGE cooling radiator for it and gallons of water which would then slow you down).

Advantages

It keeps the inlet tract nice and short and the coolers tend to flow air well and have short tubes.

It is very adaptable, it is usually quite easy to fit the heat exchanger in between the turbo and the inlet, you can site the cooling rad anywhere where it gets lots of air, you can put the storage tank anywhere on the car, even at the rear to help with weight distribution.

They are good on extended RR sessions as you can link it to the tap via a hosepipe to cool things down.

Disadvantages

They can be heavy, 1litre of water weighs 1kg, you will need about 6 to 10 litres.

They can be difficult to plumb in, you need to fit your pipe and components very carefully to avoid air locks and provide bleed valves here and there.

There are more components to go wrong.

Facts

Water takes on heat very very well, many more times efficiently than air. This is why you only need short tubes in the exchanger.
BUT (there is always a 'but' isn't there?) It doesn't give up that heat very well, in fact very slowly, this is why it is better for the engines outlined above and you have to fit a rad with a large surface area.

Types which look good:

http://www.turboneticsinc.com/produc...category_id=10

I know a guy who has one of these in his 750bhp hill climb car, it is very efficient.
There are cheap copies on Ebay, I don't know anything about them.

One to avoid

http://www.pwr-performance.com/intercooler.htm

Made in Australia and sold all over the world.
How do I know? I tested one:

[ame="http://uk.youtube.com/watch?v=cVl5Y4Z4XZg&feature=related"]YouTube - PWR Barrelcooler/Chargecooler test[/ame]

Read the text at the side of the clip.

The hot charge air is not transferring its heat to the water.
Why not? Well take a look at the so called turbulators:

They are straight through, how are these going to agitate the air and get it to exchange its heat? Answer: They don't...

Does it flow well? Heck yes, I noticed a great improvement of throttle response and lack of lag, it only lasted a short while though, after the first burst of acceleration the car was sluggish as the hot air washed in.
Note how no cooling figures are provided, if you email them they don't even have any....
It is an oil cooler core inside a cylinder of water. I had the 6 x 6, a model with a longer core and a bigger reservoir of water to go with it would have improved matters, or they can be run in tandem with an air to air unit (not great really) but it was never going to be a winner.

It went on Ebay....

So I recommended an exchanger core to try, what about cooling the water? Make your own, it needs to be BIG. An air con rad might do the job if you can fit one in, they are thin and have a massive surface area, just right for cooling water, I had a bit of a play around with one before ditching the idea - it was after all a circuit racer so no good for this type of cooling.

Interestingly, but probably of no use to you whatsoever, the integrale has a plastic tank inside the rear bumper skin, it must be used for taking the shock out of a small bump or accident, I was going to utilise this for the water storage, but the project was aborted.

I think that is all, any questions?

**AlfaJack** · 05-10-08, 08:27

Thanks for the write up

No questions about it, think its all explained.

One question about your air filter. Would you mount it there if it was your every day road car for any weather condition? I am thinking that rain water might be a problem? Is it dangerous for too much water to be on the filter?

**Evodelta** · 05-10-08, 09:13

Well it was just a mock-up to see where everything fitted, so it never got used like that. You may notice the white house rainwater pipe I used! These are quite often very good when planning pipe routes to get an idea if it will fit or what it looks like.

The K&N has a solid end with no filter there so it wouldn't get any rain head-on, the filter material is oiled cotton so I'm not sure it would let any water through, if it did it may some beneficial fine spray!

In short, for a road car, no, it's not very practical, I would site it behind the head light or maybe with some sort of sheilding arrangement.