It's basically the V8 of electric motors. Different topology results in better power to weight ratio. From the outside they look pancake shaped.

I want a V12 or V16, thank you very much.

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

If the displacement isn’t measured in cubic meters, can you even call it an engine?

Bonus points if you have to heat that crap you call fuel before you inject it into the massive cylinder.

Ok, me too now. But you can’t have that, so maybe you could settle for a high-reving V8 in a tunnel?

Then all you need is a good recording and decent headphones

A good recording and a sound system which can move the exact amount of air that the engine has moved, to be precise.

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

Stick two of them together on the same axle then.

Why do you need an axle?

Put the engine and its transmission to the wheel mounted next to each wheel.

No need for differentials etc, if they can work out a steering mechanism for each, then you've got 4WD with 4W steering.

In the video there's talk of how you can use them as regenerative braking as well, so have that as part of the wheel structure.

No axles, no differentials, independent suspension, electronically controlled power to each wheel, regenerative braking.

Gonna be a fun decade or more of innovation coming.

Wouldn't putting them in the wheel increase unsprung mass, which would degrade the feel of the car?

I think he was talking about small engines the size/weight of existing disk brake assemblies. So either no change or weight reduction.

One in every wheel