[manarth]

The translation's a little woolly.

For the AMG GT4 there will be 3 motors: two at the rear, and one at the front.

My interpretation (and my German's pretty lousy) is that each motor is combined with a gear system in a single package, and they're calling the overall package (motor plus gears) a High Performance Electric Drive Unit (HP.EDU).

The two rear motors will probably be independent, so no need for a mechanical rear diff (it'll be electronically controlled).

There's no mention of a front diff, so it's unknown whether that's built into the front HP.EDU or is a separate mechanical diff).

[chrisweekly]

In terms of traction control, does this translate to something between "4WD" and "AWD"? Or is it orthogonal?

[Gracana]

Kind of orthogonal. Traditional AWD and part-time 4WD systems are solutions to get power from a single motor to both the front and rear of a vehicle. AWD has a center differential to account for differences in front and rear driveshaft speeds when driving on high-traction surfaces. 4WD just locks the front and rear driveshaft rotation together, which is a simple and robust solution that only works on loose surfaces.

With separate front and rear electric motors, there's no center differential to worry about, and a sufficiently sophisticated motor control system can make it behave well on and off road.

[throwway120385]

This is probably the most succinct explanation I've ever read of the differences and the advantages of one over the other. I've been trying to understand this from different sources for years now.

[chrisweekly]

Thanks! Makes perfect sense. Great explanation!

[manarth]

I'm not sure that the traditional notion of traction control applies, given that there are three independent suppliers of power, so you don't necessarily need the mechanics of diffs and computer-controlled brakes to provide maximum traction.

What would it mean to "turn off" traction control in a car with independent motors per wheel? (OK this is a 3-motor/4-wheel scenario, but hypothetically…)

With software control and independent motors, we're likely to see increases in low-traction capability (for the right price-point and probably aimed at particular buyers)