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From a non-technical point of view, there is a couple of things to consider:
Is your spouse with you or not, and where are you in the starting line?
If the spouse is with you you will be nagged if you accelerate too fast all the time. So you better slow your accell and reduce heat build up in the wires, E-components, and in the verbal combat.
Starting position matters also. If you are first-line... accel quick so no others get in front of you, otherwise they will control the ability to accelerate any further.
Otherwise please don't drive too slow; we don't want to be grouped with the Prius crowd that is (or most) known for driving as slow as possible to max regen and/or to save 2 cent's in gas.
:)
 

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So the key point is to drive 'cheaply in the Bolt?
I tell people it's a hybrid. It burns electrons and rubber! (y)
Not the key point. People might want to understand what's happening under the hood, it's an engineering/science curiosity kind of thing. Safety & traffic conditions dictate a lot of driving style most of the time.
Around here, I tell people it burns 64% natural gas & coal, true if you live near CO. (36% comes from Keebler elves pedaling really hard, with no smoking breaks.....)
The coasts are better, CA is 59% nat gas, no coal.
I wonder how much quicker the Bolt would be with better tires and a re-map of the controller?
@OkieBolt has sticky tires on his, Hankook VENTUS V12 EVO2 K120 and he shaved 0.5 seconds off the 6.5 sec baseline standard (all-season tire) time. That puts the Hankook-Bolt at 0.45 g's, close to the 0.47g max (all 266 ft-lbs all the time), and beats the 0.42g baseline stock. Not bad...
U should be able to get more amps at launch without tire spin using the Hankooks with a chip tune, although the 0.45g to 0.47g isn't much already, as most of that diff is air drag !!!..... GM engineers probably limited current at launch to prevent wheelspin with standard all-season tires, keeping the traction control system brakes from having to activate too often when somebody stood on it.
 

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From a non-technical point of view, there is a couple of things to consider:
Is your spouse with you or not, and where are you in the starting line?
If the spouse is with you you will be nagged if you accelerate too fast all the time. So you better slow your accell and reduce heat build up in the wires, E-components, and in the verbal combat.
Starting position matters also. If you are first-line... accel quick so no others get in front of you, otherwise they will control the ability to accelerate any further.
Otherwise please don't drive too slow; we don't want to be grouped with the Prius crowd that is (or most) known for driving as slow as possible to max regen and/or to save 2 cent's in gas.
:)
I'm lucky, my wife likes acceleration as much as I do. Otherwise, what I get from this whole thread is, I can:

1. go back to school, get a dual PhD in Physics and Electronics Engineering, so as to come up with the perfect variable accelerator percentage by time and speed.
AND
2. drive only at 3am so other vehicles don't interfere with the aforementioned plan.

And in the end there will be no significant difference in big picture efficiency vs all the EV drivers who drive however they feel like driving, and enjoy themselves.

I like my Bolt even more now.
 

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what fancy "chip-tune" are you speaking of? please...
It doesn't exist yet. Concept-car only. I've never heard of a hot tune available.

I was saying there could be more current flow allowed at launch. Especially using sticky rubber to take advantage of max torque at launch.

And, adding to that, I guess you could allow more current to flow at speed to get the motor above it's normal standard 266 ft-lbs limit. This would mean cooling might not be enough for longevity & it certainly voids warranty. (Kind of like when Teslas at the drag strip got too hot after a couple of runs, and the temperature sensors begin to put much lower limits on the amps (current) to keep the motors & batteries from burning up.)

Also, the half-shafts & gearbox could break. This is the kind of thing the "Fast & Furious" crowd tries to get around. Here’s What Happened With The Tesla Model S Race Car That Got Too Hot After Five Miles On An F1 Track
 

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I wonder how much quicker the Bolt would be with better tires and a re-map of the controller?
I have UHP 235 Michelin tires with 18in wheels and it's definitively quicker. While it was easy to make the tires spin with oem tires when not in sport mode it's now very difficult to do so. Can still do it in sport mode though. I've also shaved some weight by removing all i could remove at the back of the car (rear seats headrests are surprisingly very heavy).
 

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...While it was easy to make the tires spin with oem tires when not in sport mode it's now very difficult to do so.
Can still do it in sport mode though. ....
OK,
Back to this question.:unsure:
Does Sport mode do more than just remap the Go pedal travel?
We know that full power is full power no matter what you do with that switch.
Is there possibly more that the Sport mode does?
I heard it also stiffens the shock dampening and lowers the car an inch!!;)
 

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OK,
Back to this question.:unsure:
Does Sport mode do more than just remap the Go pedal travel?
We know that full power is full power no matter what you do with that switch.
Is there possibly more that the Sport mode does?
I heard it also stiffens the shock dampening and lowers the car an inch!!;)
For me, from a standstill one mode gives max torque when the car is already moving (due to pedal travel) while the other mode gives max torque when the car is not even moving. The latter is enough to make the tires spin. Don't think the sport mode change suspensions in anyway or i would probably feel it as i haven't much room left with those big tires.

Here is your answer anyway:

 

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I don't know about Sport Mode, but I rigged up each of my wheels with a baseball card...I haven't timed the 0-60 yet, but it sounds as awesome as any as any Toyota Yaris with a big loud muffler(was near one on the highway yesterday)
 

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Discussion Starter #50
Fun calculation: How much thrust (force, Pounds, lb) does a Chevy Bolt produce at maximum? Usually we think of an F-15 having 'thrust' not a car, but it does, just the same.

266 ft-lbs x 7.05 gearing = 1875 ft lbs at the half shaft. Acting over a 1.06 ft tire radius = 1,769 lbf at the front wheels = 7869 Newtons
7869 Newtons force / 1616 kg mass = 4.87 meters/s2 = almost exactly 0.5 g's acceleration.
Since current & torque is limited at low speeds, you may only get 0.5 g's accel at around 20 mph or so (?). And it's limited by tire grip too, so not sure if you can actually get there. Add a driver and mass goes up, so 0.5 g's is for a hamster driver only....
It is interesting to see what can be done calculating. I had no interest in this stuff in school. I wonder if teachers are doing a disservice as I don't know if any of my teachers explained why or how these calculations could be used in the real world. It seemed to a be course after course of explanations of how to solve problems with little or no attempt to show how these things could be used.

Edit: in all fairness, maybe they did and I just didn't care?
 

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Here is your answer anyway: [Sport Mode]
From the link:
"In theory, it means that at wide-open throttle, there should be no explicit difference between Normal Mode and Sport Mode."

So, as I said, no difference in performance. Full Power = Full Power.
We could measure it and also do blind testing at the same time.
 

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correct.
Recap from the article, sport mode S vs. D (normal mode).
No changes in any systems: all the same in both modes: steering feel/response, suspension, max motor output, toque, HP.
Only remapping of the foot /throttle pedal.
 

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Discussion Starter #53
GM engineers probably limited current at launch to prevent wheelspin with standard all-season tires, keeping the traction control system brakes from having to activate too often when somebody stood on it.
Let me add too it is possible they limited power from a standstill for battery longevity. I recall reading high power from a standstill is hard on a battery and so power is limited initially.
 

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From the link:
"In theory, it means that at wide-open throttle, there should be no explicit difference between Normal Mode and Sport Mode."

So, as I said, no difference in performance. Full Power = Full Power.
We could measure it and also do blind testing at the same time.
Sure, on paper there is no difference until you take into account the tires. With stock tires there is no difference with max torque and both modes lead to wasting energy burning rubber instead of accelerating. My favorite mode with the stock tires was with traction control off on slightly wet surfaces. So much fun all the way to 60...
With better tires you start noticing differences between both modes as these can at least handle most of the normal mode torque on dry as the throttle get depressed further.
 

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....With better tires you start noticing differences between both modes as these can at least handle most of the normal mode torque on dry as the throttle get depressed further.
I don't question you get better times with better rubber.
I question any usefulness from that little switch.
And as always, it's faster if you aren't "burning rubber".(y)
 

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An EV uses the exact same amount of energy to accelerate to 60 mph whether it takes a second or a minute according to CleanTechnica.
That's a lie, and inconsistent with basic physics, both electrical and physical forces.

Ohm's law - power losses are I^2*R

Even if R is fixed (it may increase if the motor heats up, but let's assume the motor has enough thermal mass that this isn't going to be an issue unless you're in a motorsports scenario), if you floor it, higher I means much higher I^2*R losses.

Now at extremely low acceleration rates, the background drain of your electronics and HVAC will play a role, but this is only if you accelerate reeeeeeeeeeaaaaaaalllllyyyyy slow or it's the dead of winter in Canada and your heater is pegged at 7500W sustained.

There's also the fact that you have spent more time at 60 MPH and as a result, for the same distance traveled, will have fought wind resistance for a longer distance.

That said, unless you're slamming the car to 140 kW, then stopping, then slamming the car to 140 over and over again (e.g. autocross), the losses won't be significant.
 

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This way.

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All batteries have what is called internal resistance. The more current you draw, the more heat is generated (current x current x resistance or I^2R). So the less acceleration pedal input will create less internal, wasted heat energy. It should also be noted that the same internal resistance means that slower regeneration is more efficient too.
 

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That's a lie, and inconsistent with basic physics, both electrical and physical forces.

Ohm's law - power losses are I^2*R

Even if R is fixed (it may increase if the motor heats up, but let's assume the motor has enough thermal mass that this isn't going to be an issue unless you're in a motorsports scenario), if you floor it, higher I means much higher I^2*R losses.

Now at extremely low acceleration rates, the background drain of your electronics and HVAC will play a role, but this is only if you accelerate reeeeeeeeeeaaaaaaalllllyyyyy slow or it's the dead of winter in Canada and your heater is pegged at 7500W sustained.

There's also the fact that you have spent more time at 60 MPH and as a result, for the same distance traveled, will have fought wind resistance for a longer distance.

That said, unless you're slamming the car to 140 kW, then stopping, then slamming the car to 140 over and over again (e.g. autocross), the losses won't be significant.
It's true from the standpoint of the basic physics of energy required to move mass of x amount to velocity of y amount. It's also practically true from the standpoint of normal use of the Bolt. It's technically false as you point out, because of the variables you mention. They are negligible in real use.
 

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The most fuel efficient way to accelerate which will give you a higher m/kWh which will give you more miles is to pretend there is an egg between the accelerator and your foot. Keeping the energy use light green will also help.
I read on here about people complaining about not getting at least 259 miles on a charge. If they would drive more efficiently, they would easily get that and more. I don’t charge to 100% anymore since I don’t need the distance or miles, but I would see 350 miles when my m/kWh was in the high 5s or higher.
 
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