Coated Intercooler Question(s)
 

I have seen a few stock intercoolers that have been coated. My question(s) are, what coating is being used, and I also would like the pros & cons of coating the intercooler. Does this method keep a more constant internal temperature? Hence, having it coated instead of upgrading to a larger intercooler? Or have people done this solely for looks only? Any help or insight would be very appreciated. I searched and didn't find a real answer or proof of modification to IC. I may have misworded when searching too. :helpme:

Thanks, Tim

It depends what kind of coating people are putting on their IC's. Spray paint would be a bad thing because it'd keep heat in and the point of the IC is to disperse heat. Now some coating companies offer Thermal Dispersents which allow the coated surface to disperse heat faster than bare metal. I don't know how much of a difference they make but do some searching on the internet you probably won't find much help on the forum.

I would never use regular paint on the intercooler because it will just create a barrier between the ambient air and the fins.

Anodizing, which would be the proper way to color the intercooler, helps heat dissipation because it creates pours in the metal, increasing surface area IIRC.

a lot of people arent coating the IC so much as dying it. There is a chemical that you soak aluminum in that changes it colors. Im not sure of the colors available, but i have seen black on here, and i use to work at a machine shop awhile back that had a gold dye

The goal of a coated intercooler, aside from protecting it from the elements, is the raise its emissivity.

Do some googling on emissivity and you'll see why it would be quite beneficial to an intercooler, especially in situations where airflow over the intercooler is limited, but it has plenty of space into which it could be radiating heat.

Aluminum, normally, has a very LOW emissivity (like gold/silver/chrome/etc): it radiates very little of its heat for any given temperature. If you can raise the emissivity, it will disperse much more of its heat without any airflow over it at all. That's not to say it will work a lot better in conditions with tons of airflow- in those conditions the difference may be marginal. But a FMIC with a high emissivity sitting around in traffic will radiate a lot of its heat away with very little airflow.

Almost anything black will have a high emissivity, black electrical tape has one of the highest emissivities and is often used as a calibrating material with infrared thermometers. (which only measure thermal flux, not temperature) Cast iron has a fairly high emissivity as far as metals go, thanks in part to the high carbon content. Stainless steel has a fairly low emissivity. (giving it an unusual combination of low thermal conductivity and low emissivity, the opposite of what you'd want for an intercooler, but exactly what you'd want for exhaust parts) Polished aluminum has next to zero emissivity, beaten only by polished silver and, of course, Gold.

Emissivity is the inverse of thermal reflectivity, hence why Gold is often used as a thermal reflector. You could just as easily coat the outside of your headers/cast-iron-manifold with gold and they would radiate almost no heat to the surrounding environment. (conduction and convection, on the other hand ... lol) Polishing stainless steel headers would do the same job alllllllmost as well, but not quite.

Black paints, if thin enough, won't impede the conductivity of the intercooler enough to overcome the increase in emissivity. A lot of factory intercoolers/radiators are "painted" black for that reason. (borderlines on dying them because the paint is so thin)

The trick to "Thermal Dispersant" coatings is to get high thermal conductivity AND high emissivity, which are almost always mutually exclusive. My understanding, though don't quote me on this, is that they impregnate the material with strands/flakes of a material (like gold/silver) which has a high thermal conductivity, but don't allow the strands/flakes to make up a significant portion of the surface. That way, the gold/silver conducts the heat to the surface of the coating, where the high emissivity radiates it away more efficiently than the substrate itself would be capable of doing.

Important Note:

Thermal Dispersants are also excellent thermal absorbants. That means that if the backside of your intercooler is right next to your 200*F radiator, and the backside of the intercooler is coated with a thermal dispersant, instead of dispersing more heat, it will ABSORB more heat. You'd actually better off NOT coating the backside of the intercooler if it is facing a hot object; in fact, polishing it to a shine would turn the aluminum into a VERY good thermal reflector and reflect most of the heat back away from the intercooler. :)

Anyway ... read about emissivity! It's interesting stuff and google will provide you will more answers than I ever could. :beer:

-Adrian

https://www.evolutionm.net/forums/sh...d.php?t=193864

Check this out maybe some good info in here.

Check out Swaintech's BBE coating as well. It's a thermal dispersant coating that will help the intercooler to emit heat, which cools the intake charge even more. It has a semi-gloss black color to it.

http://www.swaintech.com look at "automotive coatings" then "race coatings" Swaintech is probly the best. I've heard good things about Cradin as well. http://www.cradin.com it has the same color when it's done. Here's a thread with pics regarding the Cradin coating. https://www.evolutionm.net/forums/sh...d.php?t=224598

The McLaren F1 used Gold as a heat reflector...
http://static.flickr.com/25/44491119_75c9687096.jpg

(... and everyone here knew that. :p )

If you gold plate the exhaust, it will radiate less heat too. Weird shizzle.

haha i figured...I just wanted to show off that picture :lol: