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Discussion Starter #1
Reading in the Owner's Manual did not enlighten me much on Sport Mode. One YouTube video and two comments here in the Forum lead me to believe that it "just" changes the "sensitivity" of the accelerator pedal (i.e. less foot travel/less angular pedal movement for the same increase in power). Are there any other changes? Does it lessen "regen" while coasting, braking, or "paddle-pulling"? Is it like the opposite of "L" mode? I think I read that it DOES use up battery capacity faster. Other than "fun", does it serve any other purpose? "But officer, I just had it in 'sport mode' and did not realize it would make me exceed the speed limit!"
 

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From what I seen in reviews, videos and from GM is that Sport mode just changes the profile for when you get to 100% "floored it", as in you hit 100% before the pedal gets to the bottom of its travel. I have seen no other information that relates to any other behavior changing.
 

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I would expect it's a software only feature. Actually it has to be as the accelerator is drive by wire. The brake too, until the middle/end of the stroke where it switches to hydraulic. Certainly there's no other hardware involved, so yeah it just makes it more responsive. In terms of responsiveness you have from least to most responsive

  • D mode Most like a car
  • D + Sport (haven't tried this)
  • L regular acceleration + aggressive regen
  • L + paddle Regular acceleration + aggressive regen
  • L + Sport Sensitive acceleration and deceleration
  • L + Sport + paddle Sensitive acceleration and deceleration
I've gotten tire squeals from flooring it on non sport, haven't tried this in sport.
 

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Take it out of traction control too. If you floor it with traction control on, it starts tapping brakes on one wheel or another to avoid wheel spin. I found it really weird, and a bit disconcerting never having had a car with it before. With it in sport, and no traction control, it will squeal the tires for a second or so before the car catches up with the tires, just like you would expect, without all the jerky braking drama.
 

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My Chevy sales guy insisted that Sport mode had two properties it adjusted, one was the throttle mapping and one was somehow related to traction/stability control. He'd done a sport driving event with the Bolt at a track, and this is what he was told there. However, I've never seen any other mention of the second adjustment, so I don't know if he got bad info or not.
 

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Its probably my imagination but in Sport mode my car feels quicker, more fun to drive, does anyone drive their cars exclusively in Sport?


When I had many later model corvettes turning off TC gave you a sport mode the car was more responsive and better on fuel.


I wonder if we used Sport only would we travel further on a charge?
 

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I've only used Sport Mode a handful of times, and usually when I'm in front of the line at a stop light at a multi-lane thoroughfare. The pickup is definitely noticeable compared to plain old D or L. And yes, definite tire squeal if you try to floor it as soon as it turns green. :D

It would be interesting to see how it affects the GOM if driven exclusively on Sport. (I reset my trip meter daily.) Will check it out one of these days.
 

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Discussion Starter #8 (Edited)
Its probably my imagination but in Sport mode my car feels quicker, more fun to drive, does anyone drive their cars exclusively in Sport?

When I had many later model corvettes turning off TC gave you a sport mode the car was more responsive and better on fuel.

I wonder if we used Sport only would we travel further on a charge?

Methinks it would result in less range. We all know that if we accelerate as slowly as the accompanying traffic will alow, we will increase mi/kWh (range). It would seem to me that anything that would induce us to accelerate more quickly (that Camero next to you at a stoplight) would be detrimental to range. Others want to chime in?
 

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Because of the higher acceleration? Or because of the higher average speed plus that you are more likely to use the friction brakes wht driving more sporty?
 

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Methinks it would result in less range. We all know that if we accelerate as slowly as the accompanying traffic will alow, we will increase mi/kWh (range). It would seem to me that anything that would induce us to accelerate more quickly (that Camero next to you at a stoplight) would be detrimental to range. Others want to chime in?
Sport mode only remaps the accelerator and makes it more linear. When not in sports mode they make it feel like a regular ICE (first part of pedal travel is squishy).

As for range, if you don't jackrabbit start and stop, Sport mode won't affect anything. BUT... Most people put it into sport mode to have a quicker jump off the line and a more responsive feel to the pedal, so it will reduce range.

Anytime you Regen, Accelerate, Hard steering, Brake, you are losing energy.
 

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Because of the higher acceleration? Or because of the higher average speed plus that you are more likely to use the friction brakes wht driving more sporty?
If you use max accel its less efficient versus using less peak kW for a longer duration. Even if say, assume same distance traveled and same arrival time at destination.. and even assuming braking, steering and regen losses equal in both cases. In the max accel case you have more losses in the battery, motor, and controller. Not to mention more losses in the tires when there is more energy going thru them to the road.

But its great fun so I highly recommend it. Basically you are paying pennies on the dollar compared with something like a Fiesta ST. The more you HOON the more you are SAVING in gas money!
 

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In the max accel case you have more losses in the battery, motor, and controller.
It sounds logical, I know. But is this proven or just an assumption? Could more losses during a shorter amount of time perhaps amount up to the same as less losses during a longer among of time? In other words, does an e drive train necessarily become less efficient when it needs too work harder? I seriously don't know.

Keep in mind, to a certain extend an ice becomes more efficient when to make it work harder. Nor comparing ice to e- motor, but to some this may sound equally illogical.
 

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In the max accel case you have more losses in the battery, motor, and controller.
It sounds logical, I know. But is this proven or just an assumption? Could more losses during a shorter amount of time perhaps amount up to the same as less losses during a longer among of time? In other words, does an e drive train necessarily become less efficient when it needs too work harder? I seriously don't know.

Keep in mind, to a certain extend an ice becomes more efficient when to make it work harder. Nor comparing ice to e- motor, but to some this may sound equally illogical.
Basic physics. It's the power equation. It will use more battery accelerating around quicker.

Same is true for gas cars (more gas), human beings (more calories), etc.
 

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It sounds logical, I know. But is this proven or just an assumption? Could more losses during a shorter amount of time perhaps amount up to the same as less losses during a longer among of time? In other words, does an e drive train necessarily become less efficient when it needs too work harder? I seriously don't know.

Keep in mind, to a certain extend an ice becomes more efficient when to make it work harder. Nor comparing ice to e- motor, but to some this may sound equally illogical.
You're absolutely right that an ICE becomes more efficient when nearing 75% of peak load (basically throttle position). Slow acceleration is less efficient in an ICE than brisk acceleration (not full throttle).

However, an EV is likely less efficient when quickly accelerating due to losses in the battery, wires, and motor. I expect these losses to be very minor though. In another thread I posted this motor efficiency graph, which at first glance looks like there are big differences in efficiency, but looking closely we see that at its worst, the motor is 85% efficient, and at best, 95%. That's only a ~10% difference, and only during the brief time that the motor is being pushed hard. Then around 6,000 RPM, the motor is most efficient at full torque (throttle).



...and for fun, the efficiency map of the petrol engine. Basically, the closer to the red island you get, the more efficient the engine is converting gasoline into power. In this case, 2500 RPM and 75% throttle, making about 45 HP. As you can see, even at full power, the engine is still relatively efficient compared to low throttle openings.



The full explanation here for those interested:
http://www.chevybolt.org/forum/54-chevy-bolt-ev-versus-competition/27546-infiniti-q-ev-e-power-based-serial-hybrid.html#post391114


Basic physics. It's the power equation. It will use more battery accelerating around quicker.

Same is true for gas cars (more gas), human beings (more calories), etc.
Physics says it will take more power to accelerate quickly, but the same amount of energy to reach any given speed (factors like aerodynamics excluded). In other words, in space, it takes the same amount of energy to accelerate a rocket 10 more MPH whether you do it in 1 second or 1 year.

Humans tend to burn calories based on distance traveled (or elevation gained), regardless of if they ran that distance or walked it.
 

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Huh? Go walk a 1/4 mile track for one mile with a heart rate monitor on which measures calories.

Then sprint that 1 mile as fast as you can with the same heart rate monitor.

Look at the calories (energy used) at the end.

You will use more energy sprinting that same distance.
 

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Huh? Go walk a 1/4 mile track for one mile with a heart rate monitor on which measures calories.

Then sprint that 1 mile as fast as you can with the same heart rate monitor.

Look at the calories (energy used) at the end.

You will use more energy sprinting that same distance.
Yeah, there is a slight difference. Most literature on the subject considers it equal even though it is not precisely. It depends on factors such as how fast you walk compared to how fast you run. The point though is that if you only have 1 measurement metric to go by, distance traveled predicts calories burned better than other metrics such as pace, or total time.

Increases in walking speed dramatically raise calorie burn per mile as well as per minute. Indeed, at about 12:30 per mile, walking hits a point where it burns about the same calories/mile as running. Walk faster than 12:30 and you will burn more calories/mile than running at 10:00
 

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Huh? Go walk a 1/4 mile track for one mile with a heart rate monitor on which measures calories.

Then sprint that 1 mile as fast as you can with the same heart rate monitor.
You'll use up more calories per minute, but it'll take you fewer minutes to complete. The effects come close to cancelling each other.

What jogging does better than walking is to strengthen your cardiovascular system by making it work closer to it's maximum potential.
 

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Huh? Go walk a 1/4 mile track for one mile with a heart rate monitor on which measures calories.

Then sprint that 1 mile as fast as you can with the same heart rate monitor.
You'll use up more calories per minute, but it'll take you fewer minutes to complete. The effects come close to cancelling each other.

What jogging does better than walking is to strengthen your cardiovascular system by making it work closer to it's maximum potential.
My original point relates to the question of whether accelerating in the Chevy bolt quickly (mashing the pedal) could somehow use less or the same power as accelerating slowly (feathering the pedal)..... that since you are accelerating quicker perhaps the time savings will somehow make up for the amount of power used.

Obviously the power equation is not perfect as it relates to cars... since we don't live in a vacuum of space. But I think the general physics applies. You will use more energy.
 

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My original point relates to the question of whether accelerating in the Chevy bolt quickly (mashing the pedal) could somehow use less or the same power as accelerating slowly (feathering the pedal)..... that since you are accelerating quicker perhaps the time savings will somehow make up for the amount of power used.

Obviously the power equation is not perfect as it relates to cars... since we don't live in a vacuum of space. But I think the general physics applies. You will use more energy.
I'm always reiterating this, but the laws of motion apply equally in the vacuum of space, the atmosphere of Earth, and everywhere in between. Considering aerodynamic drag, slower is more efficient.

Aerodynamics aside, and assuming this electric motor is representative of the efficiency curve of the Bolt, it seems the sweet spot is somewhere near 50% throttle. Very slight torque shows in the blue region, which is closer to 85% efficient, while half torque and midrange RPM shows 95% efficiency.



You're going to be slightly less efficient just mashing the pedal, but not enough to notice much difference in range. What hurts range is high top speed, and extensive use of regen/brakes. Acceleration can mostly be ignored.
 
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