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can you show a pic of the tool you use to fettle the ic intake?
 

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I'm not convinced you need a lot of pressure to produce a decent mist. Those personal spray misters (you manually pump to pressurize the plastic bottle a few times and it sprays a mist to cool you) can't possibly be over 60psi and the mist is fine enough imho for intake cooling. I think its more important to look at nozzle orifice size/design and pump reliability over just pump pressure. What about those in-line fuel pumps you can buy off Jegs or Summit racing catalogs? They are probably overkill for the volume/pressure???

I still think the fans + temperature switch are the simplest and most elegant solution for most road use/weekend track applications.
 

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when water evaporates or converts from liquid to gas form, it absorbs heat and pulls heat away from the air/part it contacts. (thats why those misting devices work so well.) Water can not create heat or cause an increase temperature in the part, unless the water itself is hotter then the part it touches.

When you drip water onto a sauna, it is pulling heat away from the hot rocks into the air, it is not creating heat. It is simply not possible to create heat unless you have a chemical or atomic reaction. The water is cooling the rocks, part of the energy went to converting the H20 to gas form, part of it went to warming the air/steam.

I have no idea what happened with your IAT, but Subaru would not put sprayers on IC to decrease performance & reliability of the car. Spraying outside of the IC is not as efficient as spraying directly into the intake air, but it should reduce the temperature slightly.
 

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well, you would not want to spray THROUGH the IC obviously. Not only would you get condensation inside the IC, you would pull heat from the IC to the intake air. In our application, I would put the nozzle right after the IC to finish the job of the IC in cooling the air. Most of the misting coolers are meant to replace intercoolers. Typically you use a mix of alcohol and H2o to enhance the evaporation. Spraying water/alcohol though the intake also serve to reduce detonation and allow you to to run more timing & boost.
 

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The scenario you are describing is very unlikely, unless you are spraying goo on your intercooler. When water heats up, it is going to want to evaporate. It is very unlikely that water sitting on the intercooler will build up so much that it will restrict flow sufficiently to heat up your air. 1. Water is not viscous. 2. If you air flow is not fast enough to overcome a bit of water, you have other problems. Even if air does not flow completely though the intercooler, the air flow causes evaporation. (try blowing on a bowl of hot soup) 3. again, when water heats up, it evaporates and the conversion from liquid to gas from takes significant heat away from the surface.

I still say, either spray inside the intake or add some fans and be done with it. Spraying on the IC may not harm performance, but its not worth the trouble.
 

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apk, are you planning to log temperature? how about blocking off the roof opening? (could there be some backflow out through the roof opening?)
 

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well..To me, I didn't' even have to finish watching video to know the result. :shrug: Yes of course the RLS will be better in this experiment. It has a larger thermal mass. It doesn't reflect real life because it doesn't include any flow though the heat exchanger. The rate of heat transfer "Q" is directly proportional to the mass flow rate of the air though the IC. In this video, the cool air flow rate is zero, so your rate of heat transfer out of the IC "Q" is zero. You can have the biggest IC with the most thermal mass and surface area, after 1 lap you've heat soaked if you don't have any cooling air flowing though it. I really think the biggest improvement for the buck is to increase flow. I'd put a stock IC with big ducts against a big fancy $xxxx intercooler going though the mail slot any day. The most effective part of the RLS kit are the shroud with duct adapters.


Well, aftermarket intercooler might actually help.
https://www.youtube.com/watch?v=htGndR7-1Ic
Given that experiment, I hope the better IC has lower heatsoak point and brings the IAT to under 70c.
I have some reservation about that experiment, though. The hairdryer wasn't as hot as I hoped, no inlet temperature, and maybe there should have been a fan blowing through them. And measure with/without the fan. It does indicate that the aftermarket one cools better, though. Whether it's purely due to higher thermal mass, I'm not so sure, since higher thermal mass means it'll take longer to heatsoak, but it'll also remain at that temperature for longer too cool down as well.

If the hair dryer does indeed pump out 190F(87.8C), resulting heatsoaked temperatures 125F(51.7C) and 158(70C) show clear difference.
I've personally seen IAT reach 210F(99C) with the stock setup and float around 90C at a hot track day. Leaves a lot to be desired...

On a related note, I'll be running supplemental air duct to the IC as well soon.
 

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The benefit of a larger thermal mass IC is that it keeps the temperature more steady. If you measure temp of the IC during acceleration from stand still, starting when your entire car is cold and where there is little cooling air though IC but lots of hot intake air, you'd see more of a rise in temperature in a stock IC. (And in this case I think its much cheaper and probably more effective to add a couple of fans.) In our case of the Exige mail slot design, improving the air flow makes much bigger difference. Especially if you factor in an IC is $1000+ and a shroud and duct is several hundred.:shrug:
 

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not knocking their product, they make awesome stuff. That IC is pretty sweet as well. My point is that 3 chamber shroud gets you the biggest benefit in that kit, without it, you wouldn't be able to get much benefit out of that super trick IC.
 

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Thomasio. I applaud the way you are so passionate about your product. Please don't take these comments personally: RLS make awesome stuff and, yes the intercoolers are very nice. If you want to maximize the performance of our cars, its the way to go.
However, not all of us have unlimited budgets and need to get the most performance for our money.

Our point is:given the restrictive mail slot. improving flow gets you the most benefit for the buck.

I'd take 3x flow through a stock IC, over stock mail slot flowrate with a super trick IC with 50% more thermal mass and 30% better efficiency.

(Actually, for most people, your water injection kit probably gets you the most performance gain for the buck. )
 

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I think the forced fed turbo kit (and also one
of the centrifugal sc kits, [Bemini?]) comes with a small ic with a fan.
 

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Oh yeah..I'm pretty sure the MR2 turbos comes with intercooler fan on the IC.
 

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Back to the original starting topic of testing (but still relevant to the current conversation of flow vs larger IC) One thing I would suggest is a more controlled road test. No wind tunnel needed as long as you control your conditions. One good test to do is a run of say, 5 standing max throttle starts to, say, 60 mph and log the IAT. As long as you do the standing starts within a set period of time, as short as possible of course, and make sure your intercooler goes back to equilibrium temp at idle before you start another test run, you should have a pretty repeatable test. A back to back test of different hardware configurations will give you a good idea how effective each change will do.
1. stock config
2. Stock with 4" tube shroud or 3 chamber shroud
3. Upgraded IC with stock airflow
4. Upgraded IC with 4" tube or 3 chamber shroud
5. fans.. etc.
 
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