| There is only one way to gain power, that is to add more fuel. If everything that is affected by adding more fuel is proportionally adjusted, smoking is kept to a minimum. For instance, a stock Duramax operating correctly, does not emit hardly any smoke, even under a hard pull. This is because the computer keeps everything in sync. Add a computer to modify power output (edge) and it must increase fuel pressure, lengthen the fueling cycle, and try to keep all other engine requirements in proportion, a formidable task if you think about it. White smoke at idle is unburned fuel, black smoke under heavy load is partially burned excess fuel that the engine cannot utilize. An example is the billowing clouds of dense black smoke exhausted from an unlimited diesel engine in competition. |