B47D20 & kw differences

[PsyCLown]

Hey all,

So I was wondering with regards to the B47D20 engine, I see there are various powered versions available as per the wiki page:
https://en.wikipedia.org/wiki/BMW_B47#Models

Now is the difference between these only software (until the 165KW version which becomes twin turbo) or are there other supporting parts?

Thanks