This is Arild Martinsen's 4x4 M3 from 1988 in action.
Well, it started life as an M3, and then received an X-trac transplant - hence the 4-bolt rims.
The engine is M10-derived... Whether that means it is the original S14 or even an M12, I don't know. It does have a heffin' great turbocharger bolted to it, helping make 700bhp.
It's safe to say it goes a bit.
https://youtu.be/5g8eoT0M2sI