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I can't understand why if there are 4 motors, there are just 2 transmissions.

They say 1 transmission per axle... maybe they mean 4 transmissions, which would be single speed reduction to take 12,000 RPM from the motor to ~2400 RPM (at 260 km/h!) to the wheels.

Permanent magnet motors (hence no field weakening) with a (presumably) fixed ratio transmission ... I suppose they can get away with this in a sports car with plenty of torque.
 

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No. It's actually 2 transmissions. They're like transverse style transmissions. They're not the standard longitude mounted transmissions. There are two electric motors linked to input shaft on each axle.

 

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No. It's actually 2 transmissions. They're like transverse style transmissions. They're not the standard longitude mounted transmissions. There are two electric motors linked to input shafts on each axle.
Wow. And 4 controllers, no less. I guess in a no-holds-barred sports car, you can afford to do that.

But I don't see how the electric motors interact with each other. In other words, it seems to me that this is surely two independent gearboxes (each with one input shaft driving one output shaft) in one housing. I suppose it saves on space and oil, and two less drain plugs and filler plugs (since they do the same thing at the other axle).

Having said that, maybe it's some sort of limited slip arrangement whereby if one of the paired electric motors fails, the other can take over seamlessly, although with half the power.Well, 3/4 of the power, since there are 4 motors.

Maybe all this quadruplication is to get the parts into high volume more quickly, on a vehicle that will obviously have limited sales.
 

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I'd say that you're probably dead on with that. The way I see that it'd make sense is this:

During acceleration, the back wheels would get the majority of power with the front wheels getting just enough power to pull and prevent slip at the back end. Then once the initial acceleration has been achieved, the front wheels would take over and pull the car. This would be ideal in just about all situations. When the car needs more power, full power could be given to all four motors to give maximum performance while still maintaining limited slip and traction control.
 

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you could also do torque steering on purpose (totally replacing traditional power steering). I don't know if they went this far with it but that steering would feel like magic.
 

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I can imagine that would be great for handling or reliability. I think a full electric power steering system with a steering shaft and rack is the best solution.
 

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I like converting a SL . As they are increadeble to drive . The great thing is as they age people dump them becouse of maintance costs . Parts can be had on the internet instead of MB . Many parts cross over to other models . I'm trying to find if a 4matic off a E class will fit on the SL for a all wheel drive SL ( 2 motor ) . The AMG tune is unbleaveable
 
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