Something of a practical suburban trolley with a dash of three-pointed-star class, the B-Class is still arguably the least exciting of all Mercedes products.
That, however, does not apply to the once-off creation you see here, the product of a group of trainees from the Rastatt plant in Germany, where they build the B-Class.
Plant manager Peter Wesp came up with the brilliantly impractical idea of converting a B-Class into a 289kW V8-powered rear-wheel drive monster.
The challenge was immediately taken up by technical vocational training foreman Andreas Würz, who teamed up with fellow-foreman Matthias Rieger and rounded up a team of trainees specialising in production mechanics and automotive mechatronics.
When the specification sheet was drawn up, it was agreed that the spatial concept of the B-Class was to remain unchanged.
On the outside too, there were only to be minor indications of the conversion work and the cabin was to be given an injection of class and luxury.
The team used a B 200 CDI as a starting point. While the trainees completely disassembled the car, Würz found the ideal power source: a 289kW/530Nm 5.5-litre V8, which would be mated to a seven-speed autobox.
Surprisingly, the V8 fitted snugly beneath the B-Class bonnet and they were even able to use the original engine mounts.
There were serious problems with the steering, but numerous mods eventually did the trick.
The exhaust system was a clever combination of various replacement part items, and took the form of a twin-pipe system emerging at the centre of the rear end and emitting a spine-tingling, burbling soundtrack.
As for the second major transplantation problem, namely the drive axle at the rear, it emerged that the rear axle of an older W210 E-Class would be a very good geometrical fit.
Würz and his colleagues designed a subframe, which eventually fit into the bodyshell after extensive forming and welding work, while the E-Class propshaft slotted neatly into the 'sandwich' floor.
The braking system, perforated and internally ventilated disks measuring 345x34mm up front and 300x30mm at the back, were lifted from a C32 AMG and a set of 18-inch AMG sport wheels fill the arches.
The team had recourse to a typical item from the tuner's toolbox for the suspension, installing a coil-over suspension by K&W.
Despite all these extensive modifications, the B 55 weighs just 180kg more than the base car, at 1620kg, and while no performance testing has been carried out yet, the team expects it to launch from 0-100km/h in under six seconds.
There is no word on whether any more projects like this will emerge in the future, but the team has hinted that there may be some surprises in store.