And the fastest Porsche would obviously be...

Geez, it's like lemmings to the sea.  Someone spouts off about yellow being faster and what happens?  All the rest fall in line behind this mindless drivel.  Logical sense goes out the window just because some chromatically challenged guy in a back room somewhere decides to call it "Speed Yellow"
instead of baby-barf yellow or something with a less marketing appeal.  So, since its got "Speed" in the name it must be faster, right?  Wrong!
Common sense says that the entire red/yellow end of the color spectrum signifies the presence of higher heat, right?  After all, they are the warmer colors.  So, what is the source of heat?  Friction! (duh)  It has to be friction because of the lack of evidence of any outside energy source. So, without outside energy, the only source of heat is friction (or chromatic friction as Randy so aptly noted).
Now, BLUE, on the other hand, is a cool (really cool, actually) color that signifies a relative LACK of friction.  Therefore, on equivalent cars, the blue must indeed be faster for its lack of chromatic drag as it travels through light.  Extensive studies done by the Spray Paint Institute of Technology (SPIT) show that this is, indeed, correct.  The relative speed advantage of cars in the blue end of the color spectrum is enhanced especially when the sun is directly overhead and the intensity of daylight
is at its greatest.

The performance advantage falls off in dusk and the evening hours because of the reduced light and, thus, chromatic friction.  It does reappear in the presence of artificial light if the light is near the color temperature of sunlight.  This phenomenon can be somewhat disconcerting as the blue car will leap ahead through areas of bright light, (under streetlights, for example) during the nighttime hours.  This can be an advantage to the driver of a blue car with a flashlight since merely shining the light on the hood of the car at night is good for an additional 10 mph.

Randy, I hope this gives you a new appreciation and sensitivity to the color/performance question.  Don't diminish your car's performance with an improper color selection.

Harrumph.

Carl
'70 914/6 Gemini BLUE

I would like to comment on Carl Cilker's proposition regarding car color and speed.  He has claimed Blue to be the fastest, based upon wave energies.  However, he has neglected the additional weight due to absorbed photons.  Darker colors are dark because they do not reflect light, they absorb it.  This added photon mass raises the weight/horsepower ratio and slows the car. Furthermore, those absorbed photons are turned into heat.  So, a blue car (vs. a white car, for example - - or better yet, a mirror-finish car) has to first of all store all those photons it absorbed, then it has to waste energy to convert them to heat.  Of course, I can imagine his response already.....the heat warms the atmosphere around the car, therefore thinning it, therefore decreasing aerodynamic drag.  However, I believe he would be neglecting the fact that Porsche engineers very carefully have designed the surface aerodynamics of the Porsche automobile in order to minimize eddy currents and other turbulance, and the eddy currents and turbulance created by this atmospheric temperature interface created by a dark car would nullify the surface aerodynamics, again impeding - rather than aiding - the car's potential velocity. 
 
Sincerely,
 
Phil Smith