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Discussion Starter · #1 ·
When it comes to D vs. L we all know that L gives you more regen when you take your foot of the gas, but I think there's more to it than that.

As a passenger my girlfriend noticed that D seems smoother than L. My guess is that some variation in gas pedal pressure is unavoidable, and that variation is more noticeable in L. I suspect what's happening is that the Bolt is emulating a conventional automatic transmission including the torque converter. With an automatic transmission the torque converter smooths things out more in D than L.

With the sport button the main effect people talk about is that it selects a different throttle response so that you get more power in the middle, but it ends up being the same if you floor it. In addition to that my observation is that the sport button makes it less smooth. With an ICE car sometimes the sport button makes the torque converter more locked so it does less smoothing. I guess the Bolt is emulating that too.

Have you all noticed similar smoothness trade offs? It may help to ask a passenger since sometimes you don't notice it if you're causing it.

I'm now more inclined to drive in D. When I first got the car my impression was that one pedal driving (L) was the cool new way to drive. However, is addition to the smoothness I find that I do actually get good regen just from the brake peddle. Also, with L I sometimes feel that my foot is trapped on the gas pedal. I like the brake lights to be on when I'm stopped. I also find the forward creep in D to be convenient (so you can have that slow one pedal driving with just the brake pedal ;-) ). Has anyone else migrated from L to D?

My $0.02 on how the shifter should work - there should probably be less emphasis on emulating gears of an automatic transmissions and more emphasis on making sure people understand exactly how it works, and that it's what they want. One constraint, for safety, is that by default it has to work as expected for unfamiliar drivers (car attendants, car wash people, friends borrowing it, etc.). Given that it needs to shift into "D" by default, but instead of "L" let's have "D+". "D+" would a driving mode with configurable driving characteristics. A knob for the amount of regen, another for how sporty (throttle response), and yet another knob for how smooth. Those unfamiliar would probably not go out of their way to shift into "D+", so they would be unaffected. But owners could tweak it just they way they like. How's that sound?
 

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The Bolt in no way is emulating and automatic transmission. It's all driver input and pedal control.
Sure sport mode ramps up the throttle, but it all comes down to the drivers foot on the pedal.
Take you shoe off sometime and try driving it without being on/off the pedal and see how smooth it is.
 

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I suspect what's happening is that the Bolt is emulating a conventional automatic transmission including the torque converter.
I don't have my Bolt yet, so take this for whatever little it's worth. But I highly doubt that there's any "emulation" going on. I suspect that what you're seeing is a consequence of the shorter range of accelerator travel you get in "L" mode.

Since "L" mode uses more of the top portion of accelerator travel to control the amount of regenerative braking, that leaves less travel range available for controlling the amount of power to apply. Less range means that smaller variations in pedal travel will have the same effect, making it more sensitive to small movements.
 

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I don't have my Bolt yet, so take this for whatever little it's worth. But I highly doubt that there's any "emulation" going on. I suspect that what you're seeing is a consequence of the shorter range of accelerator travel you get in "L" mode.

Since "L" mode uses more of the top portion of accelerator travel to control the amount of regenerative braking, that leaves less travel range available for controlling the amount of power to apply. Less range means that smaller variations in pedal travel will have the same effect, making it more sensitive to small movements.
Nope! It's that same pedal feel . IT has no change of input/travel like the sport mode.
Sport mode just ramps it faster where L mode only activates regen for decel control.
 

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Discussion Starter · #5 ·
Thanks for the feedback everyone.

Maybe "emulation" isn't the best term. I was just trying to convey that it was similar in some ways, but not all, even if the implementation is very different. In any case you guys are skeptical of my smoothness claim. Maybe I'm just causing regen with the small variations.

Sean Nelson, that's a good theory, with the "shorter range of accelerator travel you get in "L" mode", but drdiesel1's reply makes sense. I've noticed that shifting between D and L while driving (not regen) is hardly noticeable, which suggests that the drive portion (not regen) has the same throttle response.

Thanks for that suggestion, drdiesel1. I'll try taking my shoes off for at least a small test drive. Maybe feeling the pedal would be helpful.

I wish I had an accelerometer and a way to record the output of the gas pedal. It would be interesting to see how they are related.
 

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I think you are exactly right - Chevy engineers set the accelerator pedal response to feel familiar to new EV drivers, by mimicking the feel of an auto tranny.
Personally I usually wind up using L around town for the half-second quicker decel vs. moving to the brake pedal, and D on the highway, because it feels smoother to me.
 

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and D on the highway, because it feels smoother to me.
Can't argue with one's perceptions, but only with the facts thereof. If the progress seems smoother in D than L, then that's because the driver has to be more conscious of his right foot modulation. There's no difference in the acceleration curve, only in the decel.

IMHO, the one-pedal driving is the single best feature of the Bolt. I was just explaining the other day, why an EV? I said, "Remember driving a manual transmission in rush hour traffic? Both feet and the right hand continually moving? Then going to an automatic transmission car; how much more relaxed it seemed; only working one foot? Now, after the one-pedal Bolt, when I get back in an ICE, I think, 'Darn, that's inconvenient; having to move the foot from the accelerator to the brake and back every stop.'"

jack vines
 

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Can't argue with one's perceptions, but only with the facts thereof. If the progress seems smoother in D than L, then that's because the driver has to be more conscious of his right foot modulation. There's no difference in the acceleration curve, only in the decel.

IMHO, the one-pedal driving is the single best feature of the Bolt. I was just explaining the other day, why an EV? I said, "Remember driving a manual transmission in rush hour traffic? Both feet and the right hand continually moving? Then going to an automatic transmission car; how much more relaxed it seemed; only working one foot? Now, after the one-pedal Bolt, when I get back in an ICE, I think, 'Darn, that's inconvenient; having to move the foot from the accelerator to the brake and back every stop.'"

jack vines
Yes! I find myself sometimes wanting to use my left foot to brake in my truck just to keep my right foot on the accelerator pedal :eek:
I've become accustomed to L mode and want it in all my vehicles.
 

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I've become accustomed to L mode and want it in all my vehicles.
Yes, this is why I bought my Bolt. I've been waiting for this feature ever since the first time I drove my Honda EVPlus back in 1997. That car had great regen, but it quit at about three miles per hour. Annoying.
 

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Yes! I find myself sometimes wanting to use my left foot to brake in my truck just to keep my right foot on the accelerator pedal :eek:
I've become accustomed to L mode and want it in all my vehicles.
Back in the carburetor days, I had a couple vehicles that would stall easily, so I learned to brake with my left foot and keep my foot on the accelerator to keep it from stalling. So those old reflexes might come in handy once I get my Bolt. Which will be a loaded Summit White premier like yours!
 

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Back in the carburetor days, I had a couple vehicles that would stall easily, so I learned to brake with my left foot and keep my foot on the accelerator to keep it from stalling. So those old reflexes might come in handy once I get my Bolt. Which will be a loaded Summit White premier like yours!
You'll only need those old abilities when you drive something other than the BOLT :D
 
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