rallycol

iTrader: (4)

A watercooled intercooler why and whats one worth?

Sparks

Generally referred to as a chargecooler.

Why ? same reason as an air to air intercooler. Generally not as efficient but don't require good cold air feed like an air to air. System usually comprises of a small radiator, pump and the heat exchanger, which is basically a jacket of water, the air passes through the middle.

Bob Rawle had one on a previous car ( not a scoob ). Gained 19bhp on the rollers. This car already has an air to air intercooler but it is mostly hidden from direct air flow, so not that great.

Celica GT4s had them as standard.

rallycol

iTrader: (4)

Thanks for the info,but whats it worth secondhand?

GavinP

What part of the air/water intercooler do you have ? The heat exchanger which sits on top of the engine with the radiator cap ?

Sparks: "Generally not as efficient" - the heat transfer of water from aluminium - compared to air from aluminium is fourteen times higher...

There are some pictures on my web page below...

Thanks

Gavin

http://www.netcomuk.co.uk/~gavinp/airwater.htm

Sparks

Gavin,

Yes this is true, but the water will generally be at a higher temp than the air hitting an intercooler that has a good feed of cold air at the front of the car.. hence a chargecooler system generally wont cool the induction charge as much as an air to air intercooler that has a good air feed.

Whats it worth ? not much. couple of hundred quid maybe. Have a look at the pace website, they still sell kits I think. Best off putting the money to a good front mount...

GavinP

Sparks,

Yes, air may be lower in temperature but you are missing the point of the difference in heat transfer ability and heatsinking.

I had an original air/air unit which was replaced with the air/water. Now agreed the water is warmer than the outside ambient air so why is the intake air temperature now significantly lower in all conditions... ?

Have a look at my web page at the links at the bottom - there is some very good stuff there.

The difference in efficiency between air/air compared to air/water is all about your driving environment and average speeds.

Rallycol: BTW I paid £70 for my heat exchanger if that's what you have....

Thanks

Gavin

Sparks

hmmm, ok so you reduced your induction temp, no clear indications of gains from your web pages, presume you haven't had time to get it on the rollers.. did you remove the original IC ?

Would suggest though that a front mount IC would show greater gains ? be interesting to see..

GavinP

Sparks,

Max intake temp air/air before - 70 degrees C
Max intake temp air/water - after 35 degrees C

The heat exchanger on top of the engine is a replacement for the original intercooler rather than additional.

The dyno sheets for my car are here but unfortunately there isn't a figure just for the IC swap.

I'm not saying it is better than a front mount IC in all situations, but driving conditions can make it very effective.
Also the volume of the heat exchanger and pipework is much lower.

Thanks

Gavin

Richie1

Well there is for mine Gavin

Standard car = 204BHP/218lb.ft
Standard Car with chargecooler only = 220BHP/236lb.ft
Standard car with intercooler only = 239BHP/243lb.ft

rallycol

iTrader: (4)

The cooler is the same as on Gavin's web page open to offers!

GavinP

Richie,

What car have you got then ?

Thanks

Gavin

Sparks

Hes got a cavalier turbo like me.

The car does have an intercooler ( air to air, about the same size as an early sti ) as standard, but its almost completely hidden by the headlight and bumper. result is soaring induction charge temps. If Bob Rawle is about he will testify to that! I'm sure richie will confirm but I think his runs with the chargecooler ( air to water ) were done with the stock IC in place, the chargecooler after the IC.
The runs Richie did with an intercooler are presumably without the chargecooler and using a large front mounted IC that replaces the standard one - wheres your pic richie ?

My car has 2 heat exchangers in the chargecooler system. (before and after the standard IC). Charge temps are *alot* lower but can still hit ambient +20 degrees on hard boost ( 1.4max, about 1.2 held ). On a rolling road my charge temps will be in the 50-60 area. Running a replacement IC like richie has results in far lower induction charge temps. Best way to do it is hack the number plate space out and have a IC that fills this area in the bumper, lots of cold air.

Don't know if this applies to Scoobs as much but induction kits on the cavs are a bad idea, Bob tried one on my car and reckoned with the stock airbox it pulled harder ( more torque ) I tried and agreed! as have several others. Checking induction charge temp showed I could hit 60s on the road - sucking in hot air from the engine bay is not good! Maybe the aps cold feed kits are the way to go to prevent this on scoobs ? Although I wouldn't expect underboonet temps to be as high with an impreza.

Sparks

Yep the cones in a can are a good idea. Someone does the can in carbon fibre, stupid money but I guess that doesn't conduct heat as well..

No chargecoolers are run on a seperate water circuit, the engine coolant would be far too warm.
The rad for the cc is from an iveco truck ( I think its an oil cooler or something ). Yes flow speed is *very* important.

Umm I guess a morette kit would help a bit, but half the IC would still be obscured by the bumper. Best off junking the stock one and doing what I mentioned earlier about hacking the number plate bit out, just get a small motorbike style plate and mount it elsewhere.

Also best of chucking the management on the cav too, two main drawbacks.. it uses an air flow ( or mass ) meter and it doesn't use the map sensor for enrichment, just boost control.. That said there are very few cavs out there running management, shame because they are a sturdy unit.

GavinP

The chargecooler for an Escort Cosworth shares the coolant with the engine..... as do some trucks.

Apparently, on an Escort there is no advantage to running it on a separate water circuit from the testing carried out - although a front mounted IC is also used:

22B BBS Thread

Thanks

Gavin

rallycol

iTrader: (4)

An ex prodrive GP N rallycar {oops you ment Richie}


[Edited by rallycol - 3/6/2002 8:41:24 PM]

GavinP

Sparks,

Thanks for the info - always nice to hear about other cars and how they relate.

The photos on my web page are a little out of date and I am now using a Green Twister air filter which is like a K&N cone in an alloy case. This is fed from 80mm ducting through the wing using an adapted bass port for the inlet. This should in theory offer the best of both worlds - cone filter and cold air.

I've tried a couple of different Pipercross exposed cone filters and I came to the same conclusion as you - cold air is a much better idea.

Does your chargecooler run on a separate water circuit or does it used the engine coolant ?

From the stuff I have read about this, I think the size of the radiator and the flow of the pump is much more important than some people would have you believe.

On my setup, the radiator is roughly the same size as the stock item (different dimensions though) but the pump flows four times the amount the OE two-speed item does at full chat. There is also a one gallon reservoir.

I tried different pumps and using an oil cooler as a radiator before and it didn't work well.

The bit about the Cavalier IC being behind the headlight is interesting - do people use Morette headlights (with the driving light removed) to get round this ? Or is there a better method - other than relocating the whole unit ?

I've seen at least one Impreza using Morette headlights with the driving light removed - used to duct air direct to the intake rather than to cool the IC.

Thanks

Gavin



[Edited by GavinP - 3/7/2002 1:52:26 PM]