Wiesmann has sold around 100 MF5s since the model's introduction in 2008, but it is now left without an engine. It looks like a V10 is out of the question; the twin-turbo V8 that the next M5 will use is a far more likely candidate.
No final decision has been made yet, however, as Wiesmann says that it has several options under consideration.
An announcement will be made in a couple of months, we're told. But if it isn't to tell us that the MF5 is to get a twin-turbo V8, there may be a certain amount of hat-eating in this office...