Why not a NAME? Remember those?
The alphabet soup thing is tiresome and in some cases insipid or misleading such as both the 325i and the 330i sharing a 3.0-litre, inline six-cylinder engine though output is different. MB do the same with the C230 with a 2.5L motor. Odd.
Bikes do the alphabet soup thing too, but at least a person knows that a GSX-R750 has a 750cc motor, the R1 & R6 are a bit more obtuse but represent 1000cc and 600cc respectively.