Valve cover color effect on heat and power

[4gfun]

I am sure that it won't make much of a difference but I was reading that flat black radiates heat best....but won't that heat up the engine bay a bit more?

Which is more important for power? A cooler engine bay or a valve cover being able to release heat?

I know that we are talking tiny amounts but still want to know. Getting ready to paint my Valve cover so wanted to know.

Thanks

 

[WES_393]

I don't think people understand how heat transfer works. The valve cover cover for thermal issues is about the dumbest thing I have seen. For that to be effective in ANY manner, it's probably more for keeping water out of the spark plug galleys so you don't have a misfire with a vented hood.

Almost as dumb as using paint to trap/shed heat? Not sure if you noticed, but that's what this entire thread is about. So tell me a piece of sheet metal won't block more radiant heat than a layer of paint.

 

[Colt4G63 also]

I have numbers to backup the fact that wrinkle finish black valve covers are faster than yellow.

With this valve cover, my best 1/4 mile time was 11.86:

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With this paint on my valve cover,my best 1/4 mile time was 11.81:

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The only thing I changed about the valve cover was the paint! So there you have it, indisputable proof!

I believe it has to do with the wrinkle paints ability to dissipate more heat due to the added surface area.

 

[red_devil]

liar you changed some intercooler piping and the radiator

 

[rx7ttlm]

Almost as dumb as using paint to trap/shed heat? Not sure if you noticed, but that's what this entire thread is about. So tell me a piece of sheet metal won't block more radiant heat than a layer of paint.

Scientifically there is marrit to the black surfaces absorb/ and disapate heat faster than other colors. However most of the paint people use actually insulates more than it radiates all things being equil, GE makes some paint that is more efficient but it hasn't been comercially available in a number of years. But the problem with using a valve cover heat shield is that the valve cover doesn't need to be insulated by a piece of sheet metal. Exhaust manifolds for example do need to be insulated, as demonstrated by 95% of production cars. The idea is that the heat needs to have a reasonable pathway from the combustion chamber through various channels to leave the engine or you end up with thermal runaway (read the cooling capacity is eclipsed for a given system and you overheat or exceed the optimal peramiters for power or efficiency.) If your going to go through all the trouble to approach thermal management you should be using a small gauge piece of sheet metal and the legit motorsports gold foil as a reflective material. Breaking it down shotgun style, if your trying to improve heat transfer, don't insulate the hot items like the valve cover or the head, which is why most aluminum heads remain bare, cast iorn blocks aren't painted for thermal reasons, they are painted to prevent corrosion.

The valve cover is going to be hotter than the ambient air in the engine bay, therefore the heat tranfers from the valve cover to the engine bay. So it's about the placement of said pieces that matter. Be choosey where you use thermal insulation because sometimes you end up with the opposite effect of what you are desiring.

 

[Colt4G63 also]

liar you changed some intercooler piping and the radiator

I said "The only thing I changed about the valve cover was the paint"

Actually that setup in the first photo only did 13.50s but the valve cover paint did 11.86.

 

[red_devil]

I said "The only thing I changed about the valve cover was the paint"

Actually that setup in the first photo only did 13.50s but the valve cover paint did 11.86.

Touche

 

[Colt4G63 also]

Looking back, the suspension, the twin disk clutch and water/meth injection may have had more to do with the five hundredths of a second I shaved off, but I do think the yellow was holding me back.

 

[DSMbabyy]

I have numbers to backup the fact that wrinkle finish black valve covers are faster than yellow.

With this YELLOW valve cover, my best 1/4 mile time was 11.86:


With this BLACK paint on my valve cover,my best 1/4 mile time was 11.81:

The only thing I changed about the valve cover was the paint! So there you have it, indisputable proof!

I believe it has to do with the wrinkle paints ability to dissipate more heat due to the added surface area.

There you go! PROOF! hhahah, I always wrinkle black my valve covers, Looks good, and I think it dissipates heat a bit more too... but like the 1000 other people have said, doesnt really make a differance, strip it to bare metal if your worried about helping performance... but really, just make it whatever color you want