Engine color mojo??

[Ghoste]

So how do our professional race engine builders feel about the impact of an engine color choice affecting power output?  There are some out there who claim black keeps heat controlled and thereby combustion temps I am supposing?  Some say no paint is best, some say its all bs.
For me, just good old Chrysler orange is fine but I do wonder if our resident go to guys have opinions.   

[68pplcharger]

lol I've heard the myth of the black engine paint as well.... just a myth unless your motor is directly in the sunlight where it will absorbs light energy instead of reflecting it...  

[68charger440]

My wife says any good cook will tell you that a dark roasting pan will cook faster and more evenly than a light one.  I don't know if that is an old wives tale or the truth, but visible light waves are only a small part of the light spectrum.  So maybe there is something to it absorbing the heat differently.

[ODZKing]

So, having said that a Turquoise or Chrysler Blue engine should run cooler than an orange one. 

[68pplcharger]

So, having said that a Turquoise or Chrysler Blue engine should run cooler than an orange one.  

I'll pull my motor right away and paint it white...  

I had someone tell me my Race motor would run hot if I painted it black...  I had a black small block for fifteen years and it had the same running temp(with the same thermostat) as any other motor painted orange I've built. The dissipation of heat from a motor(liquid cooled) is from the oil and water not from the air passing over the exterior of the motor. Especially since you are blowing hot air across the surface of the motor from the radiator. The temperature delta isn't great enough, from the surface of the motor to the hot radiator air passing over it, to provide any significant cooling. A great deal of air cooled engines in modern motorcycles are painted black...   If color had such a profound effect I would think these motors would never be painted black.  

[Ghoste]

Unless the black is pulling the heat away from the engine more efficiently?   Didn't Petty always run unpainted engines?

[John_Kunkel]

I like black 'cause it doesn't show sludge as much as lighter colors. Of course, if you build absolutely leak-free motors it doesn't matter that much. 

[Kern Dog]

lol I've heard the myth of the black engine paint as well.... just a myth unless your motor is directly in the sunlight where it will absorbs light energy instead of reflecting it...  

I thought the EXACT same thing when I read the OPs first post.

[john108]

The admissivity and emissivity of Black are both high meaning that Black absorbs heat and emits heat almost equally.  White reflects heat very well.  If you want to keep something cooler that is seen by something else that is hot, paint it White.
If you want to radiate heat from a hot surface to something cooler, paint it Black.  And Black accepts heat from a hotter body, such as the sun.  Don't touch a Black Car on a hot sunny day.

[Kern Dog]

Well THAT went over my head.   

[c00nhunterjoe]

Alot of the mopar stockers and super stockers have black blocks. Must be worth something. Those guys look to squeeze every last ounce of potential power out of them.

[68charger440]

The admissivity and emissivity of Black are both high meaning that Black absorbs heat and emits heat almost equally.  White reflects heat very well.  If you want to keep something cooler that is seen by something else that is hot, paint it White.
If you want to radiate heat from a hot surface to something cooler, paint it Black.  And Black accepts heat from a hotter body, such as the sun.  Don't touch a Black Car on a hot sunny day.

Makes sense to me and validates the dark roasting pan post earlier in this thread.

[Ghoste]

So should it be flat black?   

[68charger440]

So should it be flat black?   

My guess is that while it may technically be a measurable difference in a lab environment, it would have about as much effect as the weight difference of not painting the motor at all. That is to say there are probably a thousand other things that you should care about first.

[Ghoste]

But if you were running in Stock Eliminator and you had already done those thousand things and a couple more besides and still needed to look for gains...?

[68charger440]

But if you were running in Stock Eliminator and you had already done those thousand things and a couple more besides and still needed to look for gains...?

I guess it could make a very slight diff, but I think I would have more luck running a few laps around the pits, and going to the bathroom in between runs to drop a pound or two.

[c00nhunterjoe]

But if you were running in Stock Eliminator and you had already done those thousand things and a couple more besides and still needed to look for gains...?

I guess it could make a very slight diff, but I think I would have more luck running a few laps around the pits, and going to the bathroom in between runs to drop a pound or two.

You joke, but things like that happen on heads up runs....

[68charger440]

But if you were running in Stock Eliminator and you had already done those thousand things and a couple more besides and still needed to look for gains...?

I guess it could make a very slight diff, but I think I would have more luck running a few laps around the pits, and going to the bathroom in between runs to drop a pound or two.

You joke, but things like that happen on heads up runs....

I believe it.  All is fair in love, war, and racing.   I have heard many stories of the old Nascar tricks where the motto is "It's not cheating if you don't get caught!"

[Ghoste]

After spending the amount of money and time they do in Stock to gain just .001 and a win, hell yes you would do anything else.  Those are some restrictive rules.

[don duick]

I read about this long time ago not only painted flat black the paint also needs to be of a certain thickness which I cannot remember. The same article also said that teapots are shiny metal to keep the heat in.

[XS29L]

Just my  but my woodstove is back and radiates a lot of heat. I don't believe you would ever notice a difference regardless of what color you choose. I do like the look of Hemi orange with black valve covers.

[68charger440]

Just my  but my woodstove is back and radiates a lot of heat. I don't believe you would ever notice a difference regardless of what color you choose. I do like the look of Hemi orange with black valve covers.

Touch a white car in the sunlight and then touch a black one.  The white reflects the light waves and the black absorbs them.  Heat from an engine is still a light wave, it is just not visible unless it gets real hot. Infrared goggles detect heat, but it is really detecting part of the light spectrum that we feel as heat, so it may not be much, but I believe there is some difference on an engine.

[XS29L]

I  definitely agree with example of the white car and black car. With the engine the source of the heat is from within the engine. It would be interesting to see a dyno test of an engine painted white then retest the same engine painted black. I would be shocked if one made more power then the other.

[68charger440]

I  definitely agree with example of the white car and black car. With the engine the source of the heat is from within the engine. It would be interesting to see a dyno test of an engine painted white then retest the same engine painted black. I would be shocked if one made more power then the other.

I would agree that it would be very hard if not impossible to measure it with a dyno, but with sensitive enough equipment and under tight enough controlled conditions I think there would probably be a slight temp difference between the two motors.  It would be an interesting experiment to be sure.

[HPP]

Looking at the Engine Masters series, you see a variety of colors, so it may not be too significant. However,  in a race environment where you are hoping to go rounds, does it have an impact  later when you  may not have adequate cool down time between rounds?