Plumes of mixed colors when she's floored

Yeah.......big plumes of smoke from the pipes when I stand on her.............which is really that often but worrisome nonetheless. Any thoughts?

Define "Mixed Colors"

Blue smoke? White smoke? Black Smoke? Blue + White? Diagnosis by smoke color isn't totally accurate, but white smoke generally indicates water, coolant, etc in combustion (possible headgasket) while black smoke indicates excessive fuel or oil. Are there any other indications of trouble? (overheating, cutting out under boost, general loss of performance, etc.)