HR manager Martin Spicale promised financial support, which made the project
a feasible proposition in the first place. And a "victim" (Würz) for the conversion was also soon found: a B 200 CDI which had anyway been delegated to the training workshop for learning purposes. While the trainees completely
disassembled the car, Würz went in search of a suitable engine and found what he was looking for. And no mistake: the 5.5-litre V8 developing 285 kW (388 hp) and 530 newton metres of torque was transplanted into the B-Class together with a seven-speed automatic transmission and the engine control unit. The latter proved to be quite a headache later on, as it had to be reprogrammed only to process signals from the driven rear axle.
Würz: "The V8 power unit fitted amazingly well, and we were even able to use the original engine mounts." There were serious problems with the steering, but here too, harmony was restored with a number of modifications. 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. This is where the one-off, christened the B 55 gets its typical, burbling sound – once the ignition key has been turned, all heads in the vicinity are guaranteed to swivel simultaneously in the direction of the B-Class.
Intensive perusal of parts catalogues also solved the second major transplantation problem, namely the drive axle at the rear. It emerged that the rear axle of an older W 210 series E-Class would be a very good geometrical fit. Plant manager Wesp gave the go-ahead to obtain one, and Würz and his colleagues designed a subframe, which extensive forming and welding work allowed to be integrated into the B-Class bodyshell to receive the new rear axle. Elegantly concealed within the sandwich floor, the propshaft of the E-Class also fitted into the B-Class with no further modifications.