x838nwy

+1 Besides, it's more fun to smoke a body kitted rx7 with twenty gauges and loud pipes with a stock _looking_ car.

Evo05lution

iTrader: (27)

Its a good idea, it looks really good...

But just an opinion, I think its just a waste of time and money, you have an Evo...who doesnt know its turboed, and that its fast?? You wouldnt be hiding anything...

Evo05lution

iTrader: (27)

def. agreed!!!

MM Racing

iTrader: (6)

I spent about 20 minutes searching online through Google and SAE papers and it seemed that the general consesous was that thickness. If you are an engineer then you should know better then to make dumb blanket statements like "1st year physics". If we could stay civil about this then I think this could be a potentially good conversation. There are so many more things at work here, by painting it black with assuming a conductive paint you gain a large amount of radiative energy dissapation. Not to mention just the fact of corroding the surface of the aluminum drops the thermal conductivity coefficent by a factor of 3.

Ian
Nerdy big tractor engineer.

x838nwy

Actually, I mentioned earlier, it depends on the properties of your paint. I seem to recall a 'critical thickness' for insulators the go around pipes. Up to a certain thickness, it's acutally less insulating than the pipe alone 'cos air is a pretty good insulator. A similar version to that will be able to tell you at which thickness your break even. A thicker coating would give you a better insulator (worse i/c) and that would be about the thickest coat you want. I think the equation would also give you an optimum thickness.

And that equation came up during _my_ first year engineering. (part of the reason i can't remember is). And there seems to be no magic number that works for any paint.

MANGOOK

iTrader: (3)

Car looks good man! Where in West Palm do you live? I work in Boynton Beach!

SuperHatch

iTrader: (23)

Don't sweat it Ian, there are Garbage Men out there that claim to be "Sanitation Engineers" too...

You had a bad physics teacher or are just having a brain fart which I often do. It’s very easy to mix up words when thinking about heat transfer. Darker colored objects are better emitters and absorbers of radiative heat transfer. So painting the intercooler black will increase its ability to radiatively emit and absorb heat energy.

I think you were thinking about convective heat transfer, which is the removal of heat energy via the movement of a fluid (or gas) over a surface. Intercoolers are all about convection, whether natural convection while the car is sitting still or forced convection while the car is moving. The heat energy of the intake charge air is transferred to the intercooler via forced convection while the air passes through the inside of the intercooler. The heat energy is the conducted to the outer surfaces of the IC and the fins between the tubes or bars depending on the IC type. The outside air then passes over those fins and convects the heat energy out into the outside air.

When you paint or coat an intercooler you essentially add a heat transfer step to this process. The heat needs to convect from the charge air to the AL IC mass, then conduct to the fins, the conduct into the coating, then convect to the outside air. Depending on the thermal properties of the coating this can help, slightly hurt, or severely hurt the heat transfer process. The only way a coating will help heat transfer is if it's convective properties are greater than aluminum, and it's conductive properties are equal to or better than aluminum. And to be honest with you, the conductive properties should really be better too, since any material barrier causes a drop in conductivity efficiency. If neither of these properties are better, the coating WILL hurt performance.

We don't know what paint this guy used, and therefore I can't look up the thermal properties of the paint and figure out if he helped or hurt himself.

Moral of the story.... a blanket statement saying "Coatings hurt performance" is false and only used in laziness or ignorance (which often go hand in hand).

- Steve
Nerdy big government military aircraft engineer

MM Racing

iTrader: (6)

Thanks Steve, I am glad someone else can think this through and come to the same conclusion I was trying to get across. I am sure being in aerospace you have more access to paint properties then I do. I would really like to do some "real" caculations to have directly comparable numbers.

Any chance of getting me a job at your big fancy government airplane do thingy. ;-)

MIevo8MR

iTrader: (4)

Ok. This looks like a big thread for engineers to flex their muscles.

I'm a climate control engineer = 100% thermodynamics

Condensers in an ac system are pretty much the same as an intercooler. Heat transfer of some sort. Aluminum material, tubes, fins,...all the same.

Some vehicle programs from the big 3 request for black condensers. The manufactured way of painting a condenser is black epoxy powder coating.

Process:
Wash
Dry
The condenser is negatively charged
Electrostatic charge is imparted to the powder
Negatively charged condenser + Electrostatic powder = painted condenser
Painted condenser is baked in high temp to make the epoxy powder into a glossy coating
Condenser is cured.

Reasons for paint:
1) Surface durability
2) Ensure debris (dirt, mud,...etc.) can easily come off due to the glossy coating

Discussion:
Black is not the issue. The paint properties that you use might. A light coating of black paint on the IC (no matter what type of paint) simply used to mask the aluminum will not have any substantial performance effect.

Conclusion:
If you're just using it to mask the aluminum color, you'll be ok. Don't spray it on too thick.

EVIL EVO 8

iTrader: (1)

You Dummy, Never Paint A Intercooler You Will Lose Power And Over Heat Your Turbo, And I Am Tired Of These Stealth Ideas For A Evo...., Huh?? Its A Friggin Evo, Come On Every Body Knows What They Can Do,morons...

MM Racing

iTrader: (6)

Your obviously highly educated on the subject matter and we can judge that by your imacculate sentance structure. Not everyone knows what an Evo can do, you think John Doe age 52 with his C5 Vette knows a damn thing about a 4 cylinder Mitsubishi. Keep your bashing to your self.

Thanks MIEvo, that is the info that I was hoping someone would provide. I am by no means a Heat Transfer specialist.

MR_2slo4u

iTrader: (1)

not feeling it

Doogie Howser

iTrader: (2)

I often get asked if my car is "turbo?" You'll be suprised how many people have no idea about the capabilities of the lan evo or other sports cars.

I like the idea of going stealth and I think it looks great. IF there was a proven way to coat your IC without hurting performance than I would most probably do it.

evoviiiyou

iTrader: (3)

Wow, that was fun to read! Good stuff sir

mooreboost

iTrader: (6)

I'm at Northwood University off Okeechobee and Military.

And I'm not changing it either way, so just make sure all you engineer's don't lose any sleep over it tonight, you've got another busy day of arguing over the internet tomorrow!

Thanks for all the nice comments!