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32v S4 Twin Turbo installed pics.

Old 01-05-2007, 09:14 PM
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sorry but water transfers heat 14X faster then does air

take a physics class
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Old 01-05-2007, 09:24 PM
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Air to air will work just fine though. I have a 17x12x3" core on my 200 20v. It easily supports 550 hp.
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Old 01-05-2007, 09:31 PM
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I can't wait to see some dyno charts.......8 psi intercooled.....should be good for around 450whp with equal or better torque......quite impressive!

It does seem like a water to air intercooler in the valley with a new intake would make for easier packaging and possibly more power with a more efficent intake? Which is how most twincrew-roots S/C setups do it! But John knows his stuff and if he went air to air I'm sure it will work fine!
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Old 01-05-2007, 09:31 PM
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this guy is simply amazing... that's a great feat of engineering , that kuhn pulled of here.
can't wait to when he comes out of his hiding spot and shows off some numbers
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Old 01-05-2007, 10:25 PM
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Originally Posted by RyanPerrella
sorry but water transfers heat 14X faster then does air

take a physics class
But the rate of heat transfer is limited by the heat transfer coefficient of the compressed, heated air and the available surface area inside the intercooler. Further, the addition of the water stage creates a further inefficiency in the heat transfer, as the hot air must dump heat to the water, which then must dump its heat to ambient air.

The water intercooler will only be efficient as its radiator, at a maximum.

Take a thermodynamics class.
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Old 01-05-2007, 11:20 PM
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Originally Posted by Imo000
Air-Air is more efficinet, if they are large enough, it can get near ambient. This is something that an Air-Water can never do.
Big "IF" there my friend. Not until you reach the size of something Jim Page is using on his car will you even come close:

Realize this IC goes down past the radiator. On far too many cars using air / air the coolers are just too small and in a location where they are not seeing ample air flow. I motioned ducting in my previous thread - you almost never see proper ducting on aftermarket IC setups. You almost always to on OEM stuff.

These comments are not directed towards John's car since I have not seen nor do I have the specs on John's IC setup.

Grab a cup of coffee and have a read:

Yea yea yea yea, Vortech sells air / water so they would come up with a white paper promoting the idea. As if they couldn't produce an air / air for their kits. If the cooling properties of air are so much superior to water - why did Porsche abandon air cooling?

Try this the next time you are out in the garage.
1.Heat up two equal pieces of metal to 200 degrees.
2.Blow at one with your air hose
3.Run water from your tap over the other

Care to guess which one cools off faster?
Originally Posted by patrat
The water intercooler will only be efficient as its radiator, at a maximum.

Just like in the case of an air / air IC - proper size and ducting is the key. Truth is, most people and most kits do not have proper ducting or size for either scenario so it's really a dead issue on most cars. Most people are doing either one "wrong". At least compared to how an actual car maker would do it.

I'll mention the 911 scenario again - every aftermarket 911 intercooler I see (ok, most of them) have zero ducting to the wale tale. Talk about hurting performance. Porsche put that rubber lip sealing the IC to the tail for a reason - direct air through the IC. Without that ducting the air will simply go around the IC.
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Old 01-05-2007, 11:42 PM
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Another point

With air to air you can ONLY acheive ambient AT BEST!

With air/water, or some other liquid such as a compressed coolant like R12 or some type of freon you can get below ambient, in some cases 50deg F below.

Yeah you need to have a properly integrated system and you need to make sure you have ample water supply and the proper flowing pump. You must also have a water to air, heat exchanger of appropriae size to cool the now warmer water down. Most aftermarket companies with these setups have heat exchangers about the size of a AC condenser, if not smaller.

I also dont think that running water through an aluminum core which has the compressed air on the other side is the ideal way to cool air via water. But it works, What I mean is that there is probably some other means that has yet to be discovered to use a liquid or water coolant to cool compressed air. The cores are pretty much interchangeable honestly. Thus my thinking that there is most likely a better way. I woukld imagine someone just thought lets do a reverse radiator, which is what an air/water intercooler is in short.
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Old 01-05-2007, 11:47 PM
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"""Now if you look at a equal sized cooler (and W-As are usually pretty small), the Air-Watrer can remove heat quicker but it will never get near ambient. Except if you are running ice water in the system than it will, but that's only good for racing applications."""

You mention if they were the same size? Sorry, but have you noticed that air/water intercoolers are 20%-25% the size of air/air intercoolers? They dont need to be anywhere near the same size. Dont get me wrong air/water presents its own problems, but as for packaging, and overall efficency, they are SUPERIOR!

Thank you

To Hackers point about ducting

Ducting is a big issue with air to air. Sure stuffing them in the front of the front wheels provides a good enough exhaust, but how is the ducting getting there. I would imagine he used the brake duct on the lower spoiler to act as the inlet duct but thats just speculation. (Thats what i would do offhand, although I am not sure if they would provide adequate volume.) I would also hope that there is some type of vent cover as those intercoolers will get pretty beat up if there is no debris sheild from rocks etc. Thats a simple enough problem to solve though.
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Old 01-06-2007, 12:00 AM
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I just have to say WOW, that is the best looking system I have yet to see.
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Old 01-06-2007, 12:06 AM
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The Cosworth Sierra and RS500 (kinda like a Merkur here in US) had a strange and non-intuitive metal duct right in front of the rad and IC. It seems it would be tough to guess what works best without substantial testing. Those Fords ran very hard in rally and road course work at near or above 100 hp per cylinder under regulation relative to modification. Your IC needs to work pretty well for this. I don't think I would have come up with the odd little duct thingy that Ford cooked up in a wind tunnel. With turbos the Merkur guys have figured just about ANY low restriction IC is better than none.
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Old 01-06-2007, 03:16 AM
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All I can say is ...


I'll test all I can, as thoroughly as I can & document what I can, and post the results when I'm done driving. Fair enough?
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Old 01-06-2007, 03:48 AM
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Originally Posted by killav
Any guesses on price? 10k? More? The turbos alone would set you back a chunk. Can't wait to see the power output.
$25K+ cause I was going to contract him when he was back in Kentucky to do another 2V 4.5 for me. His gold '80 had like 420HP with full boost at 3500 RPMS. John did some magic on the first car and it was ducted with twin IC's in the front of the car. He some how kept the original airbox and piped it to the TT's and brought the returns from the IC' up the front of the motor and over the fuel rails. You had to look really hard to see it was not stock!
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Old 01-06-2007, 04:28 AM
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That's a sexy looking TT setup! Should really have external WGs, however.

As far as intercooling? Air to air is probably best especially for northern climates. Also, 99.99% of all high HP street setups use air to air. Air to water would be ideal when there's little room for air to air and certain 1/4 mile dragsters.
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Old 01-06-2007, 04:41 AM
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Air to water seems to work well on my Esprit, but it's a rear engine car...

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Old 01-06-2007, 02:42 PM
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Those snorkel pieces are hand laid fiberglass. John made a dummy block, and then created a silicon mold. I think they are 6 layers of glass cloth, and are surprisingly strong. As to the price of the system, I don't have any idea. I know for a fact that the turbos alone will cost about $2500. Those IC's and the new "airbox" are custom fabbed by Corky Bell, so those aren't cheap either. I would say that in the end, it will cost more than any of the other existing forced induction options, but cheaper than a stroker build.

My understanding of intercooler theory has lead me to believe that neither is better at everything. Both AA and AW have unique benefits. AA really shines when there is little stop/start driving, because it requires airflow to cool charge. AW has an absorption property that will allow it to cool boost even when the car is not moving for a short period of time. This will heat up the liquid though, and decrease performance until it is cooled. In short, AW generally perform better on the dyno because of that function. As to which is better, it depends on your design goals. Either can be implemented successfully. Proper implementation of intercoolers is much more important than the format chosen.
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