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Rats, I was hoping that it would be better than that, not very slightly worse. That is going to put a damper on hopes that the Hwy AER is much over 200 miles. Heck, it might be less than 200 miles.
 

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Depends a lot on speed, if 80 MPH (about 28.5 kw draw), maybe just a bit over 160 miles? But if 60 mph (about 14.6 kw draw), maybe 240 miles? Maybe 350 miles or more at 30 mph? Taking a quick stab at using the ecomodder aero calculator. Tire coef 0.01, parasitic 1 kw, 28.5 sq ft area with .32 Cd, weight 3800 lbs, others default.

Also depends a lot on usable capacity. My guess is EPA rating will be right at 200 miles, but if driven at slower speeds where there isn't much aero drag penalty, range will be significantly higher than say a Tesla Model 3 with its lower battery capacity.
 

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Interesting article. Thanks for posting.

Like horsepower in the old days, the Cd numbers are always subject to interpretation. I wouldn't pay too much attention to them. The more important number will be the MPGe on US06.

My guess for the EPA range remains 225 miles.
 

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Which is what I had predicted and caught a lot of heat with others hoping if would beat the Gen2 Volt...It's not really surprising, this is what they want, "utility" vehicle with lots of room, big door openings (for Maven/Lyft) and fixed low profile roof racks...

Was hoping this would be the first Bolt article since the TM3 reveal that GM wouldn't take a crack at Tesla, guess I'll need to wait until the next one... “It reminds you of what GM can do when we’re given a deadline and set to it,”
 

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Rats, I was hoping that it would be better than that, not very slightly worse. That is going to put a damper on hopes that the Hwy AER is much over 200 miles. Heck, it might be less than 200 miles.
For city driving and highways with limits below 65 MPH, that Cd is ideal! Bring the Bolt EV to Puerto Rico!! And if I had a Bolt EV, I bet that I will get over 230 miles of range!
 

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Was hoping this would be the first Bolt article since the TM3 reveal that GM wouldn't take a crack at Tesla, guess I'll need to wait until the next one... “It reminds you of what GM can do when we’re given a deadline and set to it,”
To me, that's a bit over-sensitive. They didn't mention Tesla at all, and are touting their ability to meet an aggressive schedule.
 

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I think the weight is supposed to be about the same as gen2 Volt, around 3550 pounds. (read it somewhere, I think) If so, it might easily get in the mid 250 miles range at in town reasonable speeds/driving.
 

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Actually .312 or .32 (whatever) is very good for a CUV of it's stature (same as the Leaf?)

But the Bolt certainly can't be compared "apples to apples" to a low-slung small car! lol

WOT

 

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To me, that's a bit over-sensitive. They didn't mention Tesla at all, and are touting their ability to meet an aggressive schedule.
Yeah. I do think GM very much wanted to be first with a under $30K BEV with a 200+ mile range. A lot of this is simply PR optics. It will be, so kudos to them. In this regard, I suspect Nissan was perceived as a bigger threat to get there first. Nissan knows how to build cars and knows how to build them cheap. Tesla not so much. Now if he has said something like "and our door handles won't fall off" then I'd agree they were digging at Tesla. :D

My guess is that bragging about how fast the Bolt EV was developed will fall flat with most people, who will wonder why it took them a full four years to come up with a production car!
 

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Being more than the Volt was to be expected given the form factor.

Horrors, this will severely impact my 60 mile round trip commute. Not. :)
 

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A larger C sized interior in a smaller B sized car. That IS something special. Asymmetrical, thinner seats for more room, bigger armrest. Integrated liftgate/taillights for more cargo space. Wheels pushed even further to the corners to create more interior space. Aluminum hood, doors and hatch for lower weight, rust resistance (though repair may be more expensive?).

Lots to like. On the seats, are they still comfy?
 

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I will also point out that I think GM has a different test methodology for establishing drag coefficient.
GM measured the Volt's cd at 0.28 and everybody complained it was higher than the Prius at the Toyota claimed 0.25. GM measured the Prius at 0.30 BTW see link below. So I wouldn't put too much concern into the Bolt EV at a GM measured 0.32.

http://gm-volt.com/2009/12/04/chevy-volts-coefficient-of-drag-is-0-28-beats-prius-and-insight/
I was thinking the same thing. I realize that GM engineers have consistently tried to be as understated as possible, but as a company, GM should recognize that other companies are using their aerodynamics as a selling point. It doesn't matter that neither the Prius nor the Model S would achieve their claimed < 0.26 Cd in GM wind tunnel testing. Toyota and Tesla are going to claim that they do, and people will buy it.

That being said, even under GM's testing criteria, the 0.32 Cd still seems high to me based on the Bolt's configuration and features. My guess is that the height of the vehicle is pushing the number up during cross-sectional testing. Either way, GM engineers had to have left many aero improvements on the design room floor for it to perform that poorly.

Again, I understand that understating features and capabilities is GM's new shtick, but some of us rely on corrected aero dynamics numbers in order to estimate energy consumption and range. So it's likely that the Bolt would be < 0.28 Cd in a Toyota wind tunnel, but all we have to go on is GM's estimate. I'll wait and see what the EPA MPGe rating and range estimates turn out to be, but if those aero numbers are accurate, GM likely lost another customer.
 

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We like to treat cd as static but it's not, different shapes have different apparent cd at various speeds, cross winds change cd since the shape is not normally tested to the side.

CDA will always be more important and lastly a square box with rounded edges called a vixen motorhome achieved .3 cd in the 80's
.32 is fair for the shape, but I rather again see the bolt be longer and narrower. .32 isn't just that exciting to me.
Ah well beggars can't be choosers
 

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The Ford C-Max (Bolt is very similar in height and width....tad less on both dimensions actually) has a drag coefficient of 0.30. The C-Max is far from being called aerodynamically sleek, so it is interesting that the Bolt's CD is even higher. The Bolt is a fair bit shorter than the C-Max, so that probably hurts the number a bit. Plus the front end is stubbier.

FWIW, the Spark EV has a CD of 0.325.
 

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Being more than the Volt was to be expected given the form factor.

Horrors, this will severely impact my 60 mile round trip commute. Not. :)
+1

And to get the number lower I wonder what the Bolt would have looked like?
 

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+1

And to get the number lower I wonder what the Bolt would have looked like?
Longer, narrower, more taper on the sides near the rear. I would suggest adding 3 feet and the CD would drop to about .28
 

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Longer, narrower, more taper on the sides near the rear. I would suggest adding 3 feet and the CD would drop to about .28

dymaxion.jpg dymaxion_detail01.jpg

IOW, the Dymaxion? :)
 
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