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Do you think Chevy will install a second motor in the empty space behind the rear axle ? Is there enough room to accommodate a motor and required components ?
 

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Do you think Chevy will install a second motor in the empty space behind the rear axle ? Is there enough room to accommodate a motor and required components ?
I do. I think that is in the future plans for this platform. I know Chevy is trying to pass the Bolt off as a CUV, but I think a proper CUV will come along in the future and it will have AWD.
 

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An AWD Bolt would be quite interesting, but wouldn't they have to up the battery capacity as it would cut down range from having to use more power to turn all four wheels??

I do hope that it does end up coming out though as that'll make it all the more better. As well, other people would be able to stop complaining about wheel spin lol.
 

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An AWD Bolt would be quite interesting, but wouldn't they have to up the battery capacity as it would cut down range from having to use more power to turn all four wheels??

I do hope that it does end up coming out though as that'll make it all the more better. As well, other people would be able to stop complaining about wheel spin lol.
AWD is always less efficient than FWD, or RWD, but if you split the Bolt's current HP between the axles, say 100 hp up front an 100 hp in the rear, then the draw on the battery would be kind of the same as now, but due to mechanical and electrical losses the AWD version would not go as far on a single charge. Maybe 20 miles less. Just a guess.
 

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An AWD Bolt would be quite interesting, but wouldn't they have to up the battery capacity as it would cut down range from having to use more power to turn all four wheels??

I do hope that it does end up coming out though as that'll make it all the more better. As well, other people would be able to stop complaining about wheel spin lol.
actually if they take a page out of Tesla's book it could be more efficient than the single motor now. True you have a little extra parasitic drag due to the extra gearing and drive axles, and some extra weight to carry, but they could do as Tesla have done and optimize one motor for low speed efficiency and one for high speed, and by shifting motive duties around depending on vehicle speed actually go farther on the same battery. Not to mention more performance potential, and probably some drive redundancy.... I just wish they'd left the gate with the motor in the back of this car. I'd happily trade a little less regen for lack of torque steer, improved acceleration due to weight transfer, and some tail out fun ;)
 

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I also understand that Tesla was able to improve efficiency, performance, and range by adding another motor. Another benefit to the 2nd motor is the greater potential for regen. It would also be nice to reduce torque steer and improve vehicle balance.
 

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... Another benefit to the 2nd motor is the greater potential for regen...
I'm not so sure about the improved regen. The greater the braking force the less weight is over the rear tires, and the less traction they have to contribute to braking. If you start braking with those tires that are already light you run the risk of losing traction and getting into an "unsafe" oversteer event. As we know the auto industry tunes everything to understeer for safety proposes, and its the same reason that friction brakes are usually much smaller on the back of the car than the front, because they are doing very little under heavy braking because those tires have very little grip. Except in sports cars with extremely low CG (weight transfer effects are minimized)

Secondly, the Bolt is already dumping up to 70kW into the pack right now at max regen. That's over a 1C charge rate and even greater than its 50kW DC fast charge rate. I do know that heavy charging will reduce the life of the battery, but I don't know how duration of that charge rate plays into it. Maybe hitting it really hard for only a few moments is not as damaging as hitting it hard for an hour, or maybe it is. Long story short, I suspect that in order to safely increase the regen rate I think we'll have to wait for a bigger battery or new cell chemistry.

The current drive assembly can handle 150kW output, it should be able to brake with the same force. Even if it's only 67% efficient (read that somewhere) turning kinetic energy back into electricity at the pack that's still 100kW which is way more than what we're seeing, and I suspect that's for the purpose of conserving battery life.
 
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