Interesting video about intercoolers that could have Ecomodding applications
 

I don't know if any of you watch mighty car mods on YouTube but I saw this video yesterday
http://m.youtube.com/watch?v=f1QL9veQaNg

I watched it because I had not heard about painting your intercooler black so I just wanted to see what was up.

This is a summary of the video if you don't want to watch it.
Basically the idea is that black objects have better emissivity (I hope that's spelled right) and will transfer heat better but the questions were does it actually work and does adding the paint end up insulating instead or helping. The results ended up being that with air flow to cool the intercooler the black painted one was 3 degrees lower than the non painted one which is worse (not enough to make a difference though) HOWEVER without air flow to cool it from the fan the black painted one had an output temp that was about 40 degrees LOWER! That's good because it means when you're sitting still without air flow to cool the intercooler you can end up heat soaking it which is bad so the 40 degree improvement is great!

So I was thinking that since a radiator and intercooler work similarly to cool either the coolant or air, respectively, if you have a grille block that will allow much less air flow to cool the radiator painting it black could help considerably, especially in city traffic or in a jam on the freeway, to keep the engine from getting too hot. What do you all think?

radiators come painted black.....I thought?? my kia is black and the one I bought for the Q45 was black

Really? Cause mine isn't. Maybe it's only newer cars come that way?

Most newer ones I have seen, especially the plastic tank aluminum cores are unpainted. My 1997 Ranger is not painted. All of the old soldered together ones were painted.

regards
Mech

Found a similar video. I think the first verse of the song is "I see a radiator and I want it painted black".

www.youtube.com/watch?v=9BcJaUYE5Jw&feature=player_detailpage
FYI, my Acura TSX has unpainted aluminum for the radiator and AC condenser.

Bad mod - don't do it.
 

About 9:25 in the video they say that they gained 40C with no airflow and LOST 3C (100C drop without paint, only 97C drop with paint) with airflow.

This first condition that everyone seems so excited about - heatsoak with no airflow - would not occur. When the car is stopped the turbo is not on boost (except for maybe a second or two before you take off if you're drag racing) and is not compressing (and therefore heating) the air. The intake air flowing through the intercooler and into the engine is close to ambient, so no heatsoak for the intercooler. Also, if your intercooler is mounted in front of the radiator, the radiator fan will be drawing air through it periodically, so no heatsoak.

Almost all of the time when you are demanding boost from the turbo the car will be moving, so there will be airflow through the intercooler. But by painting it, you have lost 3C of cooling. Net result = negative effect on performance. You are spending time, effort and money to make your car worse.

For the radiator, you should not have a heatsoak condition either. When the coolant temp approaches the upper end of normal, the radiator fan will pull air through it. But if you have painted it, you have reduced its ability to bring down the temperature of the coolant. Again, a net loser. JMHO.

But if you have a grille block and there is little airflow then this would be useful.

Hmm, hmm, hmm,..

I wanna see it painted, painted black
Black as night, black as coal
I wanna see the sun blotted out from the sky
I wanna see it painted, painted, painted, painted black

Yeah!

Hmm, hmm, hmm...

Are you saying that you can increase the grillblock after painting the radiator to reduce cooling drag? The paint would help while you're at a dead stop with no airflow (radiator fan not on), but once you start moving the paint makes it harder to lose heat from the radiator. So now you need more airflow than without the paint, but you can't get it because the grillblock is bigger (smaller opening). So again, I say net loser.

But if you try it, please let us know how it turns out.

If the hood is closed and the grill is blocked, wouldnt the radiator I mean condenser be black anyway?