Take a look at this video. I painted my FMIC wondering if it was a bad thing.
Never would I think its a improvement.
I think the boys get a little confused as outlet temps went up 3 degrees after painting but I will watch again..
Please watch and confirm if interested
http://www.carthrottle.com/post/pain...-engine-happy/

 

The video claimed that when there was airflow (i.e. car moving or fan on) the difference between painted and unpainted was statistically insignificant (paraphrasing).

 

3 degrees lower with unpainted when air moving.
What do make of this?
Huge diff when car sitting. Makes no sense really.
Did factor real heat soak from rad and engine with a real heat source like a turbo.
I like the black look better.

 

I've always thought painting a IC was a bad idea only because it will restrict airflow . The air passages are small enough as it is and when you are effectively making them smaller by the thickness of the paint on all the surfaces not to mention some passages that may be clogged completely it just doesn't seem like a good idea .


I am sure the negative impact is minimal but depending on the initial quality and design of the IC itself it will vary.

 

If the primary method of heat transfer from the FMIC was radiative then painting it black would be a good thing. But the heat transfer is by conduction, not radiation, so any paint acts as insulation making it harder to move the heat from the metal to the air. You don't see the radiator or the heat exchanger on air conditioners painted black, they are left as bare metal.

Painting an FMIC black is for cosmetic reasons (and maybe corrosion resistance), it doesn't help efficiency of heat transfer.

 

Beat me to it. BTW there is a reason our cores have a blasted (rough) finish. It creates more surface area for a better conductive heat transfer.

 

Yes but part of the test, somewhat representative using a fan indicated that with paint and airflow, the difference was negligible. I really dislike the look of the IC and rad behind the black grills. I'm painting away; very lightly though