Putting one under the hood of a 135i, though, might just be the best thing you can do with the old S65 engine. My position on the 1M would be dramatically different, however, had it been fitted ...

The BMW i3 debuted on the market in late 2013, one of the brand’s first electric cars. Also available with an optional range-extending engine ... as a much easier swap on the Nissan Leaf.