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The "incomplete fast-charging network" as a low point is invalid because the buyers will charge at home while they sleep. BTW, there are more 120 and 230 VAC outlets than gas stations!
 

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We should really compare the 5-60mph times against the competition not 0-60. This better represents the real-world responsiveness of the car.

C&D measured a 6.6sec 5-60 mph time. Looks like it pretty much matches the i3 BEV.

Here're two tables for comparison:


 

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Pretty spunky vehicle.

" With the Bolt’s impressive reach, after a typical day, most owners will need only to plug in overnight. Those who venture farther afield will find that the charging network is the one arena where Chevrolet is still handily outscored by Tesla."

We can exculude 120V outlets, filling a drained battery is like filling a swimming pool with a garden hose. It would take days. Maybe in emergencies an over night trickle charge could get you to the next DCFC/CSS station.

I still prefer the comfort, safety, ease, convince and COST of the Tesla SC network if I needed to travel long distance.

Hopefully that will change with more BEV's roaming our highways as families head off to visit grand ma half way across the country.

And kudo's to GM for UNDER promising and OVER delivering. How often does that happen.
 

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Discussion Starter #9 (Edited)
We should really compare the 5-60mph times against the competition not 0-60. This better represents the real-world responsiveness of the car.

C&D measured a 6.6sec 5-60 mph time. Looks like it pretty much matches the i3 BEV.

Here're two tables for comparison:


...
In the real world of practicality, there are critical instances when you need rapid acceleration:

From a stoplight when you must change lanes ahead quickly to catch your ramp or turn. This happens when the road signs are wrong, or when somebody is in the Right Turn Only lane next to you and is going straight. If the car to your right does not accelerate quickly you will miss your turn as he will block you out.

Next is the Controlled Metering Freeway Ramps. You are at a stop, and only have a couple hundred feet to merge at freeway speeds.

Last is you are on a mountain 2 lane road. There is a line of cars behind you, and truck struggling to keep up it's speed, and refuses to pull into a turnout.

In case 1, it's 0-45mph you need. Bolt is unknown, but quick.
In case 2, it's 0-60mph you need. Bolt is 6.5s, right up there with many cars in it's price range.
In case 3, it's 50-70mph you need. Bolt is 3.5s, right up there with many cars more expensive than the Bolt.

Seems the 50-70mph testing is not readily available for the i3 without REX, but the REX is not in the same league, even in range added from the ICE generator.

Note that the i3 is more expensive at MSRP than even fully loaded Bolts, yet lacks the other metrics to compete. While the i3 has praise heaped on it for acceleration and handling, it does not exceed the Bolt in any significant area except price.
 

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Interesting article. Thanks for posting. This is probably the most important statement: "Electric cars appear to have laid down permanent roots in the automotive landscape with the first long-range, affordable EV from an established, mainstream automaker."

190 miles range at 75mph is probably the same or better than a Tesla S60. Impressive.
Almost a certainty. The S85 has a range of 228 miles at 70 MPH. Just making it linear has the S60 going 161 miles at 70 MPH (60/85 X 228). Of course we have two different testing groups, Idaho National Labs and C&D, so there is still some uncertainty. But that's a large gap at a slower speed. My conclusion is that tuning for acceleration has some downsides.
 

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We should really compare the 5-60mph times against the competition not 0-60. This better represents the real-world responsiveness of the car.
I don't understand this that well. Obviously there has to be a a rolling start for the 0-60 MPH times being faster than the 5-60 MPH times. Agree with Qinsp as to when you need faster acceleration, though "need" and "want" are likely not the same and "want" likely varies from person to person and over the aging cycle.

The only times I want faster acceleration are when I come up to a light I know is very short, I want to make a left turn followed by a right turn soon after, and there are five cars in the right lane and no cars in the left. If I go in the right lane I'm likely to miss the green and have to wait a fairly long wait for the next green. So zipping around the corner and then cutting in is a much better option as long as I don't actually cut anyone else off.

The other time is when there is a jerk at a light and I just want to be a butt head.

Neither is a need exactly but one is a more mature want!
 

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I don't understand this that well. Obviously there has to be a a rolling start for the 0-60 MPH times being faster than the 5-60 MPH times.
Here's an article that explains the difference.
http://insideevs.com/the-rolling-start-a-better-ev-performance-metric/

There are certainly situations where acceleration off the line is important, but the point is that those situations are rare and the 5-60mph times are a better, single representation of the vehicle's responsiveness, especially when compared to an ICE vehicle.
 

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Overall well done...Descent 0-60 and in particular great passing speeds where you might actually NEED it...
 

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Here's an article that explains the difference.
http://insideevs.com/the-rolling-start-a-better-ev-performance-metric/

There are certainly situations where acceleration off the line is important, but the point is that those situations are rare and the 5-60mph times are a better, single representation of the vehicle's responsiveness, especially when compared to an ICE vehicle.
Thanks for the explanation. Personally the best test would be to run 0-60 without any barke/rev trick. That is probably the best test for what happens in real life and how responsive the car will be.
 

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I wish the speed limiter was high enough to run out the 1/4 mile without hitting the speed limiter... I wonder what the 1/4 mile time would be without the limiter? If they published the whole time slip with 60' time, 1/8 mile ET and 1/8 mile trap speed it would give a good indication of what an unlimited Bolt would do in the 1/4 mile.

Keith
 

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I wish the speed limiter was high enough to run out the 1/4 mile without hitting the speed limiter... I wonder what the 1/4 mile time would be without the limiter? If they published the whole time slip with 60' time, 1/8 mile ET and 1/8 mile trap speed it would give a good indication of what an unlimited Bolt would do in the 1/4 mile.

Keith
Agreed that they should at least increase the limiter for no other reason than to market a true quarter mile time...But "wondering" what the time is would be pointless...Quarter mile is the universal standard, either you meet the standards or you don't; otherwise you can have people say "dude, my car will totally beat yours from 13MPH-34MPH!"...Yet to answer your question, other cars with 0-60 in the mid 6s get a mid 14 quarter miles...Extremely doubtful it would break the 14s...
 

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Discussion Starter #17 (Edited)
From Motor Trend's review of the 1969 396ci Chevelle:

1969 Chevelle SS396 (MT)
396ci/350hp, 3spd auto, 3.55, 0-60 - 7.6, 1/4 mile - 15.4 @ 92mph
 

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The speed limiter is not a random number. It is not to meet government demands or to get some safety rating.
The speed limiter is TO KEEP SPINNING PARTS FROM DISINTEGRATING! Remember this is a 1 speed!

Agreed that they should at least increase the limiter for no other reason than to market a true quarter mile time...But "wondering" what the time is would be pointless...Quarter mile is the universal standard, either you meet the standards or you don't; otherwise you can have people say "dude, my car will totally beat yours from 13MPH-34MPH!"...Yet to answer your question, other cars with 0-60 in the mid 6s get a mid 14 quarter miles...Extremely doubtful it would break the 14s...
 

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Discussion Starter #19 (Edited)
The speed limiter is not a random number. It is not to meet government demands or to get some safety rating.
The speed limiter is TO KEEP SPINNING PARTS FROM DISINTEGRATING! Remember this is a 1 speed!
There are a few reasons speed limiters are used. Sure, one is the driveline falling apart, but it is not the most common. Tires, stability in winds, lift, braking systems, cooling systems, etc, etc.

If it were the electric motor falling apart, the reduction gear would just be smaller. So it's something else.

My bet would be range. They geared the reduction gear to achieve the highest possible miles per kWh. This apparently gave it short gearing.
 

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I wish the speed limiter was high enough to run out the 1/4 mile without hitting the speed limiter... I wonder what the 1/4 mile time would be without the limiter? If they published the whole time slip with 60' time, 1/8 mile ET and 1/8 mile trap speed it would give a good indication of what an unlimited Bolt would do in the 1/4 mile.
Here you go, using an acceleration model based on the Car & Driver speed vs time data.

If it does 15.00 @ 93.0 mph with the limit, it'll do 14.98 @ 96.3 mph without a limit.

 
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