I don't have a name for it other than pos when something brakes or I get a new ding in it, lol. As for others, after two races my neighbor calls it the Blue Demon. And I'm sure the Toyotas and Fords I beat have a few nick names for it too but they won't be as nice as my neighbors.
EDIT: As for my explanation to vote yes, it's because even though I haven't named mine I don't see any problem with anyone naming theirs. If that's what floats their boat it's cool with me and I say go for it. In other words I don't think it's childish at all. No offense but I think it childish to think so, lol.