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Been mulling over the IC options again, and although its 99% likely I'll just stick a 9000 IC, I did come up with this as an idea and thought about running it through here to see if anyone thinks its a goer...
When I did the 9000 IC conversion on a friend's 900, we junked all the air conditioning gubbins, but its just occured to me - "what about using it to make a charge-cooler".
The air con has a large rad which fits perfectly into the gap before the coolant rad and there are gaps already there to take the plumbing. I could forget about the heater-matrix bits of the air-con and just take the pump and radiator, but instead of pumping into a matrix, make up a 'box' to fit around the existing IC and pump the cooled water through the box, thus making a charge-cooler.
Except it would be even better than a standard charge cooler becuase the coolant was being actively refrigerated.
It's a far neater solution in terms of packaging than a 9K IC, but would it actually be any good? Would the additional parasitic loss from the AC pump outweigh the benefit (bearing in mind that the current IC is only marginally better than useless)? Would the AC pump be large enough to cope at all?

If the losses from the pump would outweigh the cooling benefits, then here's a second thought - The air-con pump is actually two pumps, isn't it (coz that's how a refridgerator works). I'm guessing the majority of the power drain is the pump fighting against the pressure gradient to acheive the cooling effect. Maybe if you modified the AC pump to allow the pressure to equalise across the two halves (in effect turning it into a pure pump), then it would draw far less power. I'm not sure what the AC pump actually flows (but it would flow a lot more without the resistance of driving the compressor too).
Although you would then lose the added refridgeration benefits of using the AC compressor, you'd still have a chargecooler with a massive front rad, without having to the the body surgery necessary for the 9k IC.

Thoughts?
 

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A/c

I may be wrong but i'm sure a/c coolant is about as nasty as you can get, kinda stuff that can kill if it escapes from the system, so i'd be very carfull if you were playing about with it.

I had a slightly different thought, could you attach a second water pump to where the a/c unit sits, i dunno whether the bolt holes would line up or if you'd have to make some kind of plate, but it could be an interesting idea.

If you could make it so that as the rpm goes up more water is sprayed onto the IC it could be a goer, guess you'd need a small rad somewhere to cool the water, maybe on the opposite side of the oil cooler????

I'm hopefully going to fit a modded IC this weekend, basically 2 standard 900 IC welded together. May try the water pump idea next after i've seen the results of my first mad mission.:cheesy:
 

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The size of the stock IC is not it's only problem - it doesn't flow too well either. There is also the danger of coolant being sucked into the engine - even a pin hole would drip a substantial amount of liquid in overnight and when you came to start up - boom- hydrolock - new engine please. Air to air is simple, safe and effective.
 

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You could setup an intercooler spray to increase the cooling efficiency. Just set it up like a water injection system and have it spray when the boost comes on. I hear that 9000 and volvo intercoolers are pretty bad at flowing.
 

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trackside said:
The size of the stock IC is not it's only problem - it doesn't flow too well either.
But at least it does flow better than a 9000 IC...

trackside said:
There is also the danger of coolant being sucked into the engine - even a pin hole would drip a substantial amount of liquid in overnight and when you came to start up - boom- hydrolock - new engine please. Air to air is simple, safe and effective.
If the thing's properly pressure tested before install, this is very unlikely. If it develops a leak, it's bound to leak to the *outside* rather than into the core anyways.
 

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The use of the aircon coolant has been considered by some of the major car manufacturers (notably Ford who IIRC have a patent on this). Its only suitable for short bursts of power (ie overtaking manoeuvres) before the system starts to heat up.

Drag racers have been known to place ice on their ICs or in the cooling system for chargecoolers.
 

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Alex said:
Drag racers have been known to place ice on their ICs or in the cooling system for chargecoolers.
Without blocking airflow, that would be kinda difficult to do on a fmic or smic, but with a tmic like on imprezas a sheet of dry ice can fit very nicely
 

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trackside said:
The size of the stock IC is not it's only problem - it doesn't flow too well either.
Trus, as a unit the intercooler doesn't flow well. However that's largely due to the air-path arrangement within the IC. The core itself is very well made, with large free-flowing air channels. Saab strangled it though with restrictive end-tanks that make the air do a U-turn at one end.

The C900 IC core is freer-flowing than the 9000's IC core.

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"If it develops a leak, it's bound to leak to the *outside* rather than into the core anyways" - huh? - I had an old 900IC with a hole in it where it had corroded. If it had been surrounded in water it would have let water into the core. I'm not convinced a 9000 IC flows worse than a 900IC either - both the 2 90deg conectors and the 90deg end tank arrangement on the 900IC are flow killers - no matter how good the core is the air has to get in and out of it.
 

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trackside said:
I'm not convinced a 9000 IC flows worse than a 900IC either - both the 2 90deg conectors and the 90deg end tank arrangement on the 900IC are flow killers
If you re-read the post again, you'll see that I was talking specifically about the core, not the intercooler as a complete unit.

Any decent IC core can be throttled with restrictive and poorly designed end-tanks.

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I like the idea of using the AC condensor as a heat exchanger for a plain water/air intercooler setup. Not as experimental as using the refridgerant, but it would work very nice.

Using the windshield washer resevoir and a good bosch fuel pump, you would have a pretty good system. It would hold plenty of fluid and would be able to handle a big amount of boost before the water heats up.

Much better than the Abbott supplied heat exchanger and water pump.
 

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Isn't the A/C unit going to cut out just when you need it the most, at full throttle? And if you modify it to stay on I would think you wouldn't get enough hp gain to make it worth it after you subtract the amount of hp the a/c unit is using. I know on my N/A having the a/c on makes a substantial difference on acceleration.
 
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