I searched for this topic and could only find a small amount of info. So far from what i read is that black will represent rich, white is lean, and a lightest brown is a good a/f. I know those are probably brief, but i would like more info on how to read them in more detail. Like telling if its too hot and more specifics on how to tell if its to lean or rich. Naming colors and what they represent on the plug would help a lot.