V5?

https://en.wikipedia.org/wiki/VR5_engine

We owned an vw inline 5 Passat (quantum in North America). Good engine and synchro awd.

I'd like a 600 HP 1.5l supercharged V16 - doesn't even need to be in a car, mainly just to listen to!

https://en.wikipedia.org/wiki/British_Racing_Motors_V16

Since they're relatively compact they will probably start stacking them. Like pancakes.

Stick two of them together on the same axle then.