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Hey gang, i'm not sure if this has been discussed before, I ran the usual search strings before I made this post and couldn't find anything, so i'll have to assume the answer is no.

Anywho, back to my topic, i'm looking at getting a FMIC for the liner in the not to distant future, however the majority of kits I have seen have the metalic (chrome?) finish on the intercooler core. My question is, if I were to buy one of these cores and paint it in say a matt black finish would this adversly effect the performance of the intercooler? Ie its ability to flow air, or cool the the air effectively? Would painting it black absorb a significant amount more heat during the day to adversly effect the cooling effect of the core during the day? (we all know black absorbs heat). I want to paint it black, because I dont really feel the need to let the whole world know I've got a core.

While i'm on the topic, just two other quick questions if anyone could answer would be great. For street use is it better to use a tube and fin or bar and plate type core, and what's the difference, and finally are there any significant advantages to using a cooler with return comming back under the cooler, some people i've talked to say these takes up less piping and reduces lag and pressure drop, is this correct?

Thanks in advance for any help you can offer me guys, -Tom

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hmmm... Its a fact that anything black will absorb heat easier and not dissapate it as fast, however, im not sure how much power you would lose. tube and fin... im not sure, but u usually get wat u pay for with intercoolers. under the intercooler piping is also a good question. cant help you there, im interested in this also.

Edited by bilbo117
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Cheers for that info - so you did a 'light' coat... how about the primer. What brand was that, and how thick did you spray it?

Getting an Apexi U-bend style fmic and would like to keep the stealth look of my Stagea......

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It's in reference to computer heatsinks, but is 100% valid to this discussion, Q&A article taken from http://www.dansdata.com/io042.htm (also published in the Atomic Magazine).

Is black better?

Recently, as part of our electronics course, we learned about the properties of heat sinks. The course notes (and exam mark schemes) claim that to make a heat sink more efficient it should be painted matte black.

I understand that this would make it more efficient, but my friend and I wondered why CPU heat sinks are not painted matte black? Most other heat sinks (attached to amplifiers etc) seem to be painted in this fashion, so why not CPU heat sinks?

Peter

Answer: Your course notes are right, and they're wrong.

A black object will, all things being equal, radiate heat better than one of any other colour. However, painting a shiny heat sink black may do nothing, or less than nothing, for its thermal performance, because the layer of paint acts as an insulator. The black colour must be an integral quality of the heat sink material, or a very thin, thermally conductive layer on the outside; black-anodised aluminium is a perfect example of a good black heat sink material. It's possible to put a useful thermal black patina on copper by putting it in a hot sodium hydroxide and sodium chloride solution bath (also useful for disposing of corpses), but that's neither a quick nor an easy process, so people usually only bother doing that for copper that's being used as a thermal absorber, as in solar water heaters, not on heat sinks.

This is because the colour of the heat sink matters less and less the more air you move over it. If the sink's hanging in vacuum (like the heat radiators on spacecraft that stop their own waste heat from boiling them) then it must be matte black; if it's sitting on earth being cooled by convection then it should be matte black; if it's got a bunch of forced air cooling from an attached fan* then it doesn't matter a great deal what colour it is.

Again, all things being equal, a shiny aluminium heat sink with a fan on it won't work quite as well as a black one - but the difference will be small enough that the extra marketability of the shiny heat sink is likely to be the deciding factor.

A shiny fan-cooled copper heat sink, which can't easily be made black without pointless insulative paint, will work better than an aluminium one with the same dimensions, thanks to copper's rather higher thermal conductivity.

* Replace "an attached fan" with "driving at speed" for our purposes.

Edited by Oosh
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I used an etching primer.  Very light coat of each. Very light.

I'd say it probably makes SFA difference either way unless you put too much paint on.

i agree. i painted mine black with engine enamel out of a can, and noticed nothing, apart from newfound stealth :P

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aslong as it is a thin paint your fine, if its a thick paint it will stop air from flowing through it.

so i'd water down the paint myself or alternatively

get black mesh and put that across infront of the FMIC, just makes it harder to see and u still get maximum reflection which means less FMIC heat.

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Anything infront obviously is gonna create a airflow restriction.

If you really want the extra cooling or advantage for heat dissipation, go one size bigger in your cooler, go water spray with some form of metho/water mixture, lol weld some maddog heat fins around your cooler.

Ive always wondered if you covered your intercooler in those cpu cooling block things, you know one side is cold and the other goes hot, runs on power somehow. Wonder how that would fare?

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