Homebrew water-to-air intercooler idea
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Joined: Nov 2001
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I just browse a bunch of other forums but the reason I pointed to that post was that one of the guys there was offering a respectable sized NPR intercooler for $175.
Yes, water is a better "heat sink" for the hot air. But you need lots of flow. Then the kicker is.... The thing that everyone keeps forgetting about air to water intercoolers is that the water then has to be cooled by ambient air. The same ambient air used by air to air intercoolers. In the hot water/air portion of the water to air setup... the "heat sink" is the ambient air.
The water is just a heat transfer device / fluid. A very good one but not 100% efficient. The cooling is still done by the same ambient "heat sink" air... be it a air to air or air to water intercooler. It just that a air to water system adds more complexity for the sake of packaging concerns.
Yes, water is a better "heat sink" for the hot air. But you need lots of flow. Then the kicker is.... The thing that everyone keeps forgetting about air to water intercoolers is that the water then has to be cooled by ambient air. The same ambient air used by air to air intercoolers. In the hot water/air portion of the water to air setup... the "heat sink" is the ambient air.
The water is just a heat transfer device / fluid. A very good one but not 100% efficient. The cooling is still done by the same ambient "heat sink" air... be it a air to air or air to water intercooler. It just that a air to water system adds more complexity for the sake of packaging concerns.
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Joined: May 2001
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From: Rancho Palos Verdes, CA
Vehicle: 2008 Toyota Prius 2006 Suzuki SV650S
Trying to cool an Air/air intercooler by flowing water around the outside of it would not work. You would have to build a air/water tight box around the Intercooler, then flow MASSIVE ammounts of water through that box and around/over the air/air intercooler. You could never get "good" water flow through the air/air intercooler and it would never be "even" water flow across the whole Intercooler.
Air/water intercoolers work because they are DESIGNED to use water as the cooling medium.
For a water/air intercooler, you could use the AC front mount fluid cooler/radiator to cool the water, but you would need a VERY strong(high pressure) water pump.
It is possible to use a water/air intercooler, and can have it's advantages, but in general, a properly sized, properly located air/air intercooler will perform the same function for less money and much less complication.
If you look at "real" race applications, water/air intercoolers are rarely used outside of drag racing.
Air/water intercoolers work because they are DESIGNED to use water as the cooling medium.
For a water/air intercooler, you could use the AC front mount fluid cooler/radiator to cool the water, but you would need a VERY strong(high pressure) water pump.
It is possible to use a water/air intercooler, and can have it's advantages, but in general, a properly sized, properly located air/air intercooler will perform the same function for less money and much less complication.
If you look at "real" race applications, water/air intercoolers are rarely used outside of drag racing.
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Joined: Mar 2006
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From: Australia
Vehicle: Lancer Evo IX
Uhhh Jed, when it comes to intercooling end-tank design is as directly related to compressor efficiency as immediate-family incest 
The heater core would not yeild very good compressor efficiency.
The heater core would not yeild very good compressor efficiency.