I have a black gforce suit and I don't think its any hotter than others. The best thing about it is you can roll around in the dirt underneith the car if you have to, and the black doesn't show the dirt.

http://www.discoveryparts.com/cgi-bi...keywords=GF545

 

From a pure physics stand point a flat black surface will absorb infrared energy better than a shiny surface but it will also radiate internal or externally absorbed heat back out faster than a shiny surface with the same relative factor. So if you stay out of the sun and glare black will be cooler than silver as it will dump your internal body heat better than silver all other things being same. The other variables are very large compared to the emissivity factors.

Going to be stuck in the sun a lot? Black might not be a good choice. Sun, radiant heat from a hot fire wall or trany tunnel not a factor? Black is same or even cooler than other colors. The big factors are fit, build methods and materals

 

I wear a black nomex suit (Sparco Tech5 shiny black) with nomex underwear.
Unless you are standing in direct sunlight (like on the grid) it is no hotter than any other color nomex suit.
Bottom line, nomex is an insulator. It will be hot. Since road racing is generally done in the spring/summer/fall months it is an unavoidable consequence.

From what I understand ice racing is one of the few venues where it is a pleasure to wear a nomex suit all day.
cheers
dave parker

 

Well on my last race I bought the new Xtralight 300 Sparco suit by necessity really as my other suit did not fit me... It was the only suit available at my size so I cringed at the price but after putting it on I was convinced that this is an unreal suit and worth every penny! It feels like you are wearing your pajamas and has tons of ventilation! I could not believe that I was wearing a 3 layer suit, it felt so soft, thin, light and most importantly I could feel very cool inside the suit! At Sebring with the cool temps I was actually cold inside the car!!!
Its expensive but if you can find one to try on, I'm sure you will spend the money...

 

I have the same Sparco X-light in black and it is a great suit. Very comfortable and cool. Just be careful taking it on and off as the zippers can occasionally break.