Water - air intercoolers

[matsondawson]

Anyone considered them for the vr4, for that extra low pressure drop and shorter pipe work?

[matsondawson]

Like this... frozenboost.com (http://www.frozenboost.com/product_info.php?cPath=16&products_id=1006&osCsid=80fa40ef2c68653019d4f52d9ca76924)

only us $299

[bradc]

I had, but I couldn't think of a place to mount one that would actually work! How would you do the piping?

[Nick Mann]

I think the intercooler would be easy to fit, but the radiator could be an issue? Surely the intercooler can go anywhere, but the radiator will have to go where the current intercooler is.

TBH I have never seen one of these sytems before - it looks interesting, IF it can fit!

[Turbo_Steve]

Subaru Legacy (old style) Turbo runs a chargecooler system (water/air intercooler) as standard. Even with a tiny heat exchaner on top, it's extremely effective: certainly more so than an air/air intercooler of the same size.

Have a look at Bream on LancerRegister. Has an early evo using this technology, and very effective it is too.


The radiator shown is massively oversized: something that fits in the stock intercooler location should suffice with adequate airflow: water will sink an incredible amount of heat, and will reliquish is fairly easily too, if you keep air flowing accross it.
The drawback with the smaller radiator is the chance of heatsoak increases. A fan will help, though, and bearing in mind that the subaru standard item is about 300x200x40, and will work comfortably on a 350bhp car, doesn't seem to heatsoak and doesn't have a fan of it's own.

Something twice the width and the same height with the right flow rate should comfortably go to twice that.

However, if you CAN place a huge rad & fan like that, then you're laughing....heatsoak? What's that?! :)

Reasons for:
Less space occupied
Better boost pipework & flow
Massively more efficient that air/air, and will smooth out saturation points, unlike an air/air unit. Assuming it's a road car, you can compensate for an undersized radiator with a larger resevoir. Doesn't work on track/race etc.
There's also the option to slap icecubes in your resevoir before your big drag-run :D

Reasons not to:
It weighs more what with all that water.
If it leaks, things heat up, rather than a boost leak which just costs power.
Youve an extra component to fail (the pump).
it usually costs more (the kit above is pretty close, though!).
You have to remember to keep it topped up.

[matsondawson]

Those of us with manuals have a little extra space, so move water resevour from the front right into the back of the car, put the air filter there, move the battery into the back, and with a little bit of tidying you have bulk space. Just a matter of redirecting cool air to this area. Maybe drawing it down off the bonnet, or over from where the original intercooler was.
I like the idea of mounting it as far back as possible.

I have thought of mounting two smaller radiators in the rear at the front of the wheel arches where the cool air gets forced up off the tires at speed. Once again getting a better weight distribution. Or at the rear of the front wheels with vents coming off the side.

[psbarham]

if you fill it with antifreeze (neat) it gives even more efficiency, we used to do this to the big cat dozers and trucks , and the power gains were quite impressive, if its good enough for an ice rink then its good enough for an engine

[Turbo_Steve]

Really? I thought water was actually a better heatsink than Antifreeze...hence the need to mix the two for an engine.
I don't know either way, just interested!

[Nick Mann]

Pretty sure that antifreeze is a better transferrer of heat than water. I can't remember what it said on the back of the bottle that I have used this afternoon, but the wording certainly suggested that.

[zedy1]

This dont look good to me, if the cores get corroded and water gets into the air core this can cause water into the engine

[matsondawson]

Pretty sure that antifreeze is a better transferrer of heat than water. I can't remember what it said on the back of the bottle that I have used this afternoon, but the wording certainly suggested that.

From here http://www.mr2supercharger.com/IntercoolingPage5.html

"Incidentally, note that pure water is best - its specific heat value is actually degraded by 6 per cent when 23 per cent anti-freeze is added! Other commonly available fluids don't even come close to water's specific heat value."

[Turbo_Steve]

That's what I thought: Antifreeze reduces the freezing point, but usually lowers the boiling point too. It does have excellent Anti-corrosion properties, though, and so remains essential, even in a chargecooler. Generally I've used it in fairly mild concentrations, though, just enough to retard freezing.
I'd be surprised if you got that near the specific heat value of water in a chargecooler anyway. Unless you're running massive boost or are way outside the efficiency range of your turbo(s).

[matsondawson]

This dont look good to me, if the cores get corroded and water gets into the air core this can cause water into the engine


I've tried to find reference to this online without much success. I guess if it's a problem there should be an anti-corrosive added to the water, maybe a sacrificial metal of some sort would help, or maybe some system could detect the leak. And finally I guess regular maintenance. It probably wouldn't be too hard to remove the core and inspect it. Hopefully any initial leak would show itself from rough running and if you were switched on you could stop driving.

[Turbo_Steve]

A small quantity of Antifreeze really works just fine, Matson: the subaru ones never have a problem: 25% mix usually suffices.

Also, it's not the same as a cars coolant system, as there is a lot less air present, which generally helps. For upto 300bhp I'd suggest that a 1L resevoir is perfectly adequate, so 2L should offer plenty of comfort. For optimum results, try and get the resevoir into some airflow to really keep the temps down.
Favorite location on early evos is the drivers side bonnet vent.

[matsondawson]

Hey, I ain't saying antifreeze is a problem... 6% for a 25% mix is a gnats fart :) or a nuns fanny, or whatever the expression is :P

[matsondawson]

Interesting post on anti-freeze here http://www.gi.alaska.edu/ScienceForum/ASF6/680.html

Apparently 100% anti-freeze has a higher freeze point than 60% anti-freeze 40% water... Goes against what I thought it would do.

uploaded/616/1200190866.jpg

[Turbo_Steve]

Hey, that's neat!

If you can get a really good seal, you could run the whole system on Ethanol. Boils at extremely low temps, so a totally different radiator would be required, but you just can't be phase change for 'sucking up' a lot of heat.

[phosty]

Or maybe try one filled with paraffin wax:

http://www.autospeed.com/cms/A_1815/article.html?popularArticle

Need to make sure that the cruising charge temps are below 52 degC but boost temps are above 52 degC though......

[Nick Mann]

Interesting thread this. And my head just got brought back to it from another thread going on at the moment.

Anyway, cruising around the net shows some interesting ideas:
Barrel chargecoolers are available in different sizes but seem to be more expensive than universal replacement ones. I assume that they work better from the blurb and the price but I don't know that.
56600

Universal replacement chargecoolers seem to fit some older ford turbos and a fair few VAG 1.8T applications so seem to be more readily available and cheaper to buy.
56601

One other off the wall idea (It would take some sorting though!) comes from a 1.4 FSI Golf. The chargecooler appears to sit on top of the plenum:
56602

All food for thought. The radiator could be dropped in anywhere - passenger side between the foglight and plastic arch liner, or even further back down the car, maybe near the AYC pump? Or just in front of the rear bumper? Stick a small pump in, a spare header tank and some water lines connecting it all and you have a system that could be better than an expensive intercooler.

[jayp]

It might sound like a radical idea, but rather than water, what about refrigerant? As in from the air con system, that gives a massive drop in temp across a relatively small matrix for the cabin.

So long as everything is sealed, so the refrigerant can't leak, you could even program it to maintain a steady temp, just like the climate control does in the cabin.

Sent from my HTC Desire S using Tapatalk 2

[Gowf]

The cost of a chargecooler has a lot to do with its design. There are a lot of them out there that claim to work but very few that actually do (the PWR ones are the real deal). This is because the cheaper ones are simply air/air coolers surrounded by a fluid, which is pants! The pwr ones use a different design to make to utilise the maximum possible convection. Then you also need to look at your radiator as it is the only way you are getting rid of the heat, and so you may want to consider a twin pass rad.

As for using water, you can now get ones specifically designed for drag using ice. Refrigerant can be used but you are going to need a pressurised system, which you do not need for using water, etc.

[Davezj]

i would have thought that unless the system was designed and pipe work routed correctly then it would have to be a pumped system, which is not difficult to do but adds slight amount of complexity.

[Nick Mann]

Pumping is no big deal, Dave. £15 for a pump and supply it with 12 volts.....

[Mark 4]

I work with refrigeration stuff all the time. Don't know a great deal about it but my suppliers do.

Certainly sounds like a good idea. I'll have a chat with a couple of them.

[Davezj]

i thought of sacrificing the air con for a cooling pump a while back but then i love my air con particularly in the summer months.

[Gowf]

You do need a pump yes, but it has been proven (in the MR2 world) that the bosch pumps that people use do not give you an acepable flow rate. This is why for the stocked MR2 with a GT35 I am using a standard GT4 charge cooler pump, much bigger but actually works

[blodeaxe]

Use AC to cool the charge coolers water bottle.

[Gowf]

Use AC to cool the charge coolers water bottle.

Where do you put the rad for it? And how do you implement it into your AC system?? Seems like a lot of work for very little gain.... Also, you dont need a water bottle, a small fill tank does the job.

[blodeaxe]

http://autospeed.com/cms/title_The-Patent-Files-Refrigerated-Intercooling/A_110600/article.html

Read here