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http://youtu.be/f1QL9veQaNg

The results are interesting. As noted in the video at the end emissivity works both ways so it could soak up more heat especially on a top mount configuration.

Wow, I always thought the paint may act as an insulator.

It doesn't make sense. I wish they would explain that. I just watched that right before you posted it. I'd never even heard that myth before. I thought the whole thing was a joke at first. What kind of temp drop is expected from a tmic and fmic on average/ballpark? My 06/07 wrx tmic consistently removes 30 degrees when the intercooler is not heat soaked and you're just cruising. Obviously when I stomp on the gas the turbo outlet temps jump up to 260F+ and the fmic outlet temps don't rise much at first.

Their tmic was filled with similar crusing temp heat and removed 38 degrees with no airflow through the core! More than mine with 70 mph wind!

Actually I just realized the airflow through my tmic is massively higher cfm than any hair dryer so its completely uncomparable. Still would be nice to know other peoples results.

I should get that same temp setup you have Kimo, see what the differences are with a front mount.

Yeah its easy to install and not too expensive if you compare it with other temp monitoring units.

I've noticed that, I just have to scan your superlongassbuildjournal to find the link LOL. Not going to buy it until after the car is running tho.

Haha might want to grab a beer, it's a long read.

Ok, so let's start with the fundamentals of what they were testing; emissivity. This YouTube video can explain things better in the short amount of time compared to me typing a book.

http://youtu.be/gueQrS6ORI0

The oversimplification of their test is that an intercooler painted black will lose AND gain radiant heat better than a plain intercooler.

The piece they did mention briefly, but didn't spend enough time in my opinion is that there are three modes of heat transfer, conduction (heat transfer through direct physical contact of objects), convection (heat transfer between more than one fluid or a fluid and physical object (a fluid can be a gas or a liquid)), and radiation (heat transfer via energy other than the visible spectrum, typically infrared). Each component of heat transfer, conduction, convection, and radiation makes up the total heat transferred from or to an object.

The amount of heat transferred via conduction or convection is typically much larger than the heat transferred via radiation. This is demonstrated in their test when no air is flowing over the intercooler and the primary mode of heat transfer is radiation. However, when air is flowing over the intercooler the primary mode of heat transfer is convection and is MUCH larger than radiation; hence the very small difference in temperature between the painted and unpainted intercooler. Actually, painted intercooler had one degree less temperature difference. You could chalk this up to instrument measurement error or it could be from the paint and the fact the paint does put a very small layer between the metal and the air.

Think of the paint and the intercooler metal as two walls next to each other. Heat now has to flow through the metal and the paint to escape vs. before it only had to flow through the metal. As mentioned the difference is likely negligible in the real world.

The other thing they also touched on briefly is that having a black intercooler, it also can absorb radiant heat better as well as dissipate it. So for a TMIC, a black intercooler may absorb more of the infrared heat from the engine compared to a plain intercooler. Keep in mind that once you start moving again the intercooler would likely shed that heat pretty quickly since the radiant mode of heat transfer is much less than convection.

I guess the point I'm getting to is I wouldn't necessarily recommend going out and painting your intercooler black and expect any huge differences on street driven car. Keep in mind that if this really was the next best thing to sliced bread you would see racing teams and factory sports cars come with painted or anodized black intercoolers....and you typically don't.

kimokalihi wrote:...Obviously when I stomp on the gas the turbo outlet temps jump up to 260F+ and the fmic outlet temps don't rise much at first.

Their tmic was filled with similar crusing temp heat and removed 38 degrees with no airflow through the core! More than mine with 70 mph wind!

Also, keep in mind their temperature measurements are in degrees Celsius and is not a direct one-to-one comparison to Farenheit

I watched the video and read your explanation and I think I understand but I think mcm was not clear on this at all. They made it sound like the color black made the intercooler dissipate or gain absorb heat faster/easier but the video directly stated color has nothing to do with it. Its simply the material itself that determines how easy the intercooler or object transfers heat. Correct? So painted metal transfers radiant energy better than plain metal.

For the tape example the color shouldn't affect emissivity. However, different color paints can have different emissivity, which will affect the amount of radiant heat absorbed or dissipated. The link below shows some examples of different color paints and their emissivity. Without knowing what is in the paint, my suspicion the pigments in the paint also play into what the actual emissivity is of the paint.

http://www.betterinsulationsolutions.com.au/roof

If you look at the emissivity numbers, even the white paint has a much higher emissivity when compared to bare aluminum. So the white paint in the link above may not be as good as dissipating/absorbing radiant heat as the black paint, but it's still better than bare aluminum.

I'm sure there are much more intricacies that I don't know or have forgotten, but I still stand by my point that I wouldn't suggest running out and painting your intercooler in the hopes of gaining mad horsepower.

I plan to paint or anodize my fmic if I ever get one but just to hide it.

Yeah....I kind of would like mine to be hidden, but that means pulling everything out again, I don't really want to do that.

Haha I understand. What company made your cooler and how much was it? Could they make me a custom one that would fit in the bumper with little to no cutting?

Bell Intercoolers. My thread has more info and their website.

http://www.bbs.legacycentral.org/viewto ... 89#p260589

It cost $438, plus $16 shipping in 2008. The core was 1.5" thick, 8.5" tall, and 18" long. The size would be dependent on what available cores they have. I don't think they have the radiator cores listed on their website, so I would suggest contacting them to see what they have to offer.

Are you running the AC condenser? If not, my best suggestion would be to run a tall and skinnier radiator that fits in the place of the AC condenser. If you take measurements and pictures of the condensor and if they have a radiator core near that size they could probably make a plug & play type setup. The big question is going to be whether they have radiator core that would work in that space.

The vertical radiator core support kind of gets in the way with mounting something on the bumper beam and having it extend rearward towards the engine radiator.

Spendy but it would be worth it to have an intercooler than fits as best as possible with no wasted core space sitting behind the bumper skin not getting any airflow.

When you say radiator, are you referring to an intercooler? I think I've decided against an awic but not 100% decided yet. I was thinking custom built intercooler with a reverse mounted manifold for nice short pipes.

I am referring to the radiator exchanger for my AWIC system. Bell Intercoolers should be able to do either.

Interesting video. Thanks, Josh.

I had read an article by an automotive engineer that was written many decades ago and it had to do with painting engine components black to keep the engine cooler (I'm using layman's terms here). To accomplish that, there were a couple of important points to keep in mind: 1--Flat, non-insulating paint had to be used (paint that was glossy or insulating increased the engine heat), 2--a thin layer of paint was required (too much paint insulated the engine or engine component too much, and again, the engine would run hotter).

It was of interest to me since at that time I was driving a modified air-cooled VW. I painted several engine components with a thin layer of non-insuating black flat paint. While I didn't take measurements before or after, I could tell the difference by the running of the engine, its sound, its performance, the smell, etc. The engine definitely ran cooler.

https://www.youtube.com/watch?v=z_mmmXTbLP0

MCM's mythbusting, mythbusted? Oh yeah, basically what Josh said in his 2nd post, but with piktars!

Makes sense to me. I always wanted to paint mine black just to be stealthy.

mike-tracy wrote:https://www.youtube.com/watch?v=z_mmmXTbLP0

MCM's mythbusting, mythbusted? Oh yeah, basically what Josh said in his 2nd post, but with piktars!

Nice! I beat him to the explanation by not quite a month since his video was published in July