Flat blacked the intercooler...
Nov 30, 2005, 02:00 PM
#61
Evolved Member
iTrader: (14)
Join Date: Jun 2004
Location: Nashville
Posts: 1,168
Likes: 0
Received 0 Likes
on
0 Posts
Originally Posted by SuperHatch
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
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
The paint (the cheap *** spraypaint that I used and evidently the topic creator used) is NOT a good conductor of heat therefore painting the intercooler will result in a decrease in efficiency...that is why I clarified that anodizing the intercooler would NOT hurt the performance. We're on the same page here, just not communicating very well.
and for the record, I am not a sanitation engineer. I hold a bachelor's degree in Industrial Automation Engineering. I am also 3 classes away from a 2nd degree in Mathmatics....and I am an ex navy Electronics Technician. So please don't dismiss me like Im some wise *** teenager living at home with mommy.
Nov 30, 2005, 03:13 PM
#63
Evolved Member
iTrader: (23)
Join Date: Mar 2004
Location: NJ
Posts: 2,044
Likes: 0
Received 0 Likes
on
0 Posts
Originally Posted by Evillusion
and for the record, I am not a sanitation engineer. I hold a bachelor's degree in Industrial Automation Engineering. I am also 3 classes away from a 2nd degree in Mathmatics....and I am an ex navy Electronics Technician. So please don't dismiss me like Im some wise *** teenager living at home with mommy.
Jan 13, 2006, 08:32 AM
#64
Evolved Member
iTrader: (41)
Join Date: Sep 2004
Location: Toms River, NJ
Posts: 4,653
Likes: 0
Received 0 Likes
on
0 Posts
Unless your painting the intercooler to "better" the performance, I think its completely retarded. The car comes stock with an intercooler and youre going to try and hide it? Thats pretty lame IMO. While I will say the stock IC looks somewhat fugly, just get a nice big one to take up the whole front :-)
Jan 13, 2006, 07:23 PM
#66
Evolved Member
Join Date: Apr 2004
Location: Aberdeen, NJ now in Ca.
Posts: 541
Likes: 0
Received 0 Likes
on
0 Posts
When I painted mine (I got pulled over 3 times in the first 2 weeks) and removed the wing at the same time, I used satin black laquer with a very light coating. Do not use something like a VHT brand because it has Silica and Ceramic particles in it and will prevent heat transfer.
ps I bought the EVO for what it can do, not for what every 16 year old thinks it can do.
ps I bought the EVO for what it can do, not for what every 16 year old thinks it can do.
Jan 13, 2006, 07:40 PM
#67
Evolved Member
iTrader: (3)
Join Date: Aug 2005
Location: Fort Myers, Florida
Posts: 563
Likes: 0
Received 0 Likes
on
0 Posts
I would think that painting the IC black, especially in hotter climates (I'm in SW Florida) would have a profound effect on the cooling ability of the IC, especially in stop and go driving when direct sunlight is hitting the IC and reduced airflow at slower speeds keeps the core temp up. Most a/c condensers and oil coolers are not exposed to direct sunlight. They're ducted and pushed back in the nose. The IC is right out there and is exposed to direct and reflected sunlight. I'd imagine that at constant speed, ie. highway, the airflow is substantial enough to keep the core temps down.
Jan 17, 2006, 10:20 PM
#75
Evolving Member
Join Date: Aug 2004
Location: Alpharetta, GA
Posts: 268
Likes: 0
Received 0 Likes
on
0 Posts
To those flaming black FMIC's, shame on you! What's wrong with adding a sleeper effect to your car? Yes I know the evo is not an easy car to make a sleeper but not everybody knows what an evo is and not everybody wants their car to scream "Hey I'm turbo-charged!"
Here's an example of how a black FMIC can look sick. My friends old 03 WRX with APS FMIC and SR40 turbo. He was actually considering swapping hoods with an impreza 2.5rs as it was not needed to cool the top mount, but sold it for an 04 STi. On the road it appeared to everyone that it was just a stock turbo WRX with exhaust and he surprised a lot of high horsepower cars.
Here's an example of how a black FMIC can look sick. My friends old 03 WRX with APS FMIC and SR40 turbo. He was actually considering swapping hoods with an impreza 2.5rs as it was not needed to cool the top mount, but sold it for an 04 STi. On the road it appeared to everyone that it was just a stock turbo WRX with exhaust and he surprised a lot of high horsepower cars.