While these videos may be several years old at this time, this is still a pretty wild build. I’ve seen people put a Porsche engine in a T1 Bus before but shoving a W12 into a T3 is that much more metal (or mental).
This Bus came from the factory with a ~50hp engine but that wasn’t enough for the owner. He acquired a W12 for an Audi D2 A8 and with some tuning, it now pushes closer to 465hp. In addition, the front and rear A8 axels were swapped over, a 5sp Tiptronic was installed, and it’s lowered on H&R Cup springs and Koni Sport shocks. The interior has leather Recaro seats from a Volkswagen T6 Transporter and it sits on 20in BBS wheels. This thing is legit.
In the following video, skip to :30 to hear the sounds of the W12 and in the 2nd one, skip to 1:00. Enjoy