I have gotten some information on dynoing the Crossfire. Evidently on Mercedes, there is a Dyno mode. It has to be activated using the STAR system at a Mercedes dealer. I am assuming a Crossfire also has this mode. I'm not sure if Crossfire dealers have the STAR system (diagnostic tools), but I assume they do since they need it to work on the Crossfire engine. I would try calling the Crossfire dealer and asking if they can enable the dyno mode for you, or ask for more information on it.