David,

you grumpy ??

all 215's and 218's ( + 210, 217 and 219 proto) share the same body. ( L = 16.400mm ) all 216's are 16.000mm long and 1900 hp.

The 215 is an intermediate solution as the 218 (V164) was not ready yet.
the trainheating testing with electric generator were not finalised so it was decided to built on the body of a V164 (=the later 21 the power and heating system as built and proven in the V160.
The first 10 units were proto's with 1900 hp and were numbered 215 according to the new numbering system from the start. Number 215 -002 had an engine of 2500 hp ( cut off aT 2150 HP) as planned in the 218. The series received 1900 hp and steam trainheating systems.

Jacq