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Discussion Starter #1
Greetings!

I'm sure many of us are aware of the effects that driving in L has, particularly in regards to battery regen, and slowing down the vehicle without using the brakes. My question is, How does is acceleration affected by driving in L as opposed to D?

My drive is 7 miles on surface streets, and I often shift into L for slowing down, but then back to D when the light turns green. Is there a benefit to this, or will I do just as well staying in L?

Thanks!
 

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There is NO, ZERO NADA affect on acceleration.
 

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You can still slow the car down using the brake pedal without engaging the "brakes". You're just modulating the regen using the brake pedal. L just means you'll be regenerating 100% if you let off the gas pedal.
 

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Discussion Starter #4
You can still slow the car down using the brake pedal without engaging the "brakes". You're just modulating the regen using the brake pedal. L just means you'll be regenerating 100% if you let off the gas pedal.
But I like to coast, as my traffic isn't expressly stop & go. It's not as easy to do in L.
 

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But I like to coast, as my traffic isn't expressly stop & go. It's not as easy to do in L.
Just keep it in Normal D. Coast as much as you like and use the brakes when needed. Maximizing regen usually hurts your range. Minimizing regen (like your coasting in D) usually helps your range. Sport mode feels peppier, but it just remaps the accelerator to do more with less pressure. but mashing it to the floor in L, D or asport mode accomplishes the same thing. The car won't go any faster. Now if you got lighter wheels and tires, or smaller wheels and tires, you can imove your acceleration a little. If you shed all the weight (around your belly, plus strip out everything in the interior except the driver's seat, you will get a little enter acceleration. But the simplest way to achieve a big boost in acceleration is to trade the volt in for an ELR, CT6 Plugin, or Tesla
 

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As BAZINGA says, no affect on acceleration. The motor/generator can’t do both at once. If your foot is on the accelerator using the motor to maintain or increase speed, you can’t also be using it as a generator (regen).

However... on the surface streets, do you immediately shift into L to slow down after taking your foot off the throttle, so to speak, or do you usually coast in D a little before reaching that point where L slows you down faster? Remaining in L all the time will modify these driving habits. Taking your foot off the accelerator will slow you down faster at once, so you might try to maintain speed longer until you’re closer to where the use of L will start slowing you down faster... or perhaps you’ll slow down too much and will need to put the foot back on the accelerator to reach the stop sign/traffic light...

One set of D/L regen habits might not be any more efficient overall than another... Note that D and L both engage the generator when coasting (regen). Coasting in L generates more electricity than coasting in D by using more of the car’s momentum to generate electricity, slowing it down faster. Coasting in D might not slow you down as fast, but if you spend more time coasting, the result may be the same amount of regen. The Volt has a blended braking system, increasing the "slowing down" of the car as you depress the pedal until the point where friction braking starts participating or takes over the job... and of course the paddle has its own regen setting...
 

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You can still slow the car down using the brake pedal without engaging the "brakes". You're just modulating the regen using the brake pedal. L just means you'll be regenerating 100% if you let off the gas pedal.
You'll be only slowing using regen, but nowhere near all the regen available. More like .... 25%. D "coasting" is about 10% of available regen, and the paddle on a Gen 2 is about 75%, based on the kw on the meter. Our volunteer tester got peak 5 kw from D, 15kw from L, 45kw from the paddle and just under 60kw from the brake pedal.
 

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I don't want to hijack this thread but I have a D vs L question. I have a 2014 Volt and we just completed a 1500 mile 4 day round trip to NY. I did all the driving whereas the wife usually uses this as her daily driver. I consider myself very knowledgeable as to most of what there is to know with the car. Here's my Q. I like to drive in L primarily for the lack of usage of the brakes. I keep an eye on other cars and may tap the brakes occasionally to let them know mine work but I also enjoy the relative smoothness this gives me in congested areas. A lot of our driving on this trip was on I-95 and keeping the car in L during heavy traffic made it much easier to control my pace vs braking and accelerating like the vast majority of ICE cars; much like driving a 'stick'. Well, the wife took offense to this as I've not been able to convince her that L doesn't mean what it means in most cars since the Volt is basically a 1 speed. I explained that there's no 'good label' to explain what L means since we can't use R (for regen) again. Don't even ask about my attempts to explain Mountain, Sport and Hold. She said 'show it to me in the manual' so I pulled up the pdf and showed her Chevy's description of all the modes but she then said that L should only be used for slowing down. I explained that it has no impact on steady state driving or accelerating but since I can't find that in the manual she refuses to believe me. SO, can someone point me to a thread or lend some input on how best to explain this to a very non-tech savvy person?
 

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I thought I would like L but I'm a D driver with a lot of brake.

I ride it medium to heavy all the way coming up to a light. Takes getting used to because you stop short with the wrong amount of brake.

I like to coast. I used to put my '61 chevy truck in neutral back in the 70's, got to make the most of the gas because it's up to 25 cents!

This car keeps me occupied, always calculating and figuring the right mode and driving method.

I save my battery for the ride home in the heat, don't want to park in the heat with no battery.
 

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I've only used L a few times. I don't care much for it. The acceleration didn't seem any different.

I feel that 'D' is much safer and a little more efficient if used properly. L mode in Gen 1 does not light up the brake lights when you let off the gas. D allows much greater coasting, which is more efficient. (Remember that converting energy is not 100% efficient. It's better to keep kinetic energy kinetic)

On flat roads: Coasting > Regen > Friction Brakes
 

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I don't have to deal with much traffic where I live so don't use L much in daily driving. I've also found that using L more than using the brakes prevents the rear brakes from working, as regen is only on the front wheels. My rear rotors were rusting and getting rough from non-use! L is however very effective when descending mountain passes. No brakes required. Further, you can use L and cruise control in mountanous terrain and the regen will maintain your speed downhill. Very nice feature.
 

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There is NO, ZERO NADA affect on acceleration.
My 2012 has demonstrated that L does, (albeit mildly), alter acceleration mapping too.
By switching bw L and D at lower, (steady), throttle settings, I've noticed a definite change in acceleration, accompanied by an appropriate change in output displayed on the dash.
I don't know if there is any change to full throttle output
 

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SO, can someone point me to a thread or lend some input on how best to explain this to a very non-tech savvy person?
When I bought my 2012 Volt just over 5 years ago, the salesman used "seasick mode" to describe driving in L. Perhaps this is what your wife objects to... the transition from moving to slowing down is more jerky than smooth. It’s fine for the driver, who’s expecting it, but not so comfortable for a passenger. Best use I’ve found for L is to keep the car at a steady speed using Cruise Control when heading downhill. The following is my understanding of how the Gen 1 Volt handles regen (Gen 2 has two planetary gears and may differ in operation). I would appreciate feedback if I have it wrong...

I think of the Volt as a 1-speed when "going," and D and L are for "slowing down as you coast," or "D"ecent coasting vs "L"ousy coasting. The Gen 1 Volt’s primary traction motor is a marvelous thing. When electricity flows through the coils, the motor’s shaft turns, and via the connection to the drivetrain, the turning of the motor’s shaft applies torque to the wheels, making the car move down the road. When the foot comes off the accelerator, the wheels continue to roll, and if they’re still connected to the motor via the drivetrain, they can apply torque to turn motor’s shaft, transforming it into a generator. Can’t do both at the same time.

Of course, shift into Neutral, the connection is broken, the wheels continue to go round, and the car coasts down the road because of the momentum of the car.

With the foot off the accelerator, the car’s momentum is harnessed to turn the generator shaft, which consumes the car’s kinetic energy and slows it down. By adjusting the generator’s circuits to increase or decrease the output (the regen), one controls the amount of torque required to turn the shaft, using up the car’s kinetic energy slower or faster. In D, the "slowing" effect of the regen is minimal (but still, more than if you shifted into Neutral). In L, you get more regen, and you slow down faster. The Volt’s motor/generator is not connected to the brake lights, so using regen to slow the car won’t light up the brake lights, and that can be dangerous if the car behind you doesn’t know you’re using electricity, not friction, to slow your car rapidly.

The Volt uses blended braking (starts with regen, ends with friction), so the brake pedal, one could say, gives the driver the ability to manually adjust the "slowing down" setting until you reach the point where the friction brakes are applied. The brake pedal is the only "regen level" device that is also connected to the brake lights.

Next, of course, comes the part where the Gen 1's gas engine gets clutched to the smaller motor/generator, and generates electricity to fuel the primary motor to give your Gen 1 Volt "electric-like" performance when the battery is depleted or you switch into Hold mode...
 

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When I bought my 2012 Volt just over 5 years ago, the salesman used "seasick mode" to describe driving in L. Perhaps this is what your wife objects to... the transition from moving to slowing down is more jerky than smooth. It’s fine for the driver, who’s expecting it, but not so comfortable for a passenger. Best use I’ve found for L is to keep the car at a steady speed using Cruise Control when heading downhill. The following is my understanding of how the Gen 1 Volt handles regen (Gen 2 has two planetary gears and may differ in operation). I would appreciate feedback if I have it wrong...

I think of the Volt as a 1-speed when "going," and D and L are for "slowing down as you coast," or "D"ecent coasting vs "L"ousy coasting. The Gen 1 Volt’s primary traction motor is a marvelous thing. When electricity flows through the coils, the motor’s shaft turns, and via the connection to the drivetrain, the turning of the motor’s shaft applies torque to the wheels, making the car move down the road. When the foot comes off the accelerator, the wheels continue to roll, and if they’re still connected to the motor via the drivetrain, they can apply torque to turn motor’s shaft, transforming it into a generator. Can’t do both at the same time.

Of course, shift into Neutral, the connection is broken, the wheels continue to go round, and the car coasts down the road because of the momentum of the car.

With the foot off the accelerator, the car’s momentum is harnessed to turn the generator shaft, which consumes the car’s kinetic energy and slows it down. By adjusting the generator’s circuits to increase or decrease the output (the regen), one controls the amount of torque required to turn the shaft, using up the car’s kinetic energy slower or faster. In D, the "slowing" effect of the regen is minimal (but still, more than if you shifted into Neutral). In L, you get more regen, and you slow down faster. The Volt’s motor/generator is not connected to the brake lights, so using regen to slow the car won’t light up the brake lights, and that can be dangerous if the car behind you doesn’t know you’re using electricity, not friction, to slow your car rapidly.

The Volt uses blended braking (starts with regen, ends with friction), so the brake pedal, one could say, gives the driver the ability to manually adjust the "slowing down" setting until you reach the point where the friction brakes are applied. The brake pedal is the only "regen level" device that is also connected to the brake lights.

Next, of course, comes the part where the Gen 1's gas engine gets clutched to the smaller motor/generator, and generates electricity to fuel the primary motor to give your Gen 1 Volt "electric-like" performance when the battery is depleted or you switch into Hold mode...
My wife get's car sick if I drive in L, having tracked my Corvette's I have gotten car sick when a I would ride with a buddy on the track, but behind the wheel I was in control and had no difficulty. Some folks are very sensitive to these undulations. So I brake with the pedal and modulate my braking as needed nice and smooth.
 

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Just keep it in Normal D. Coast as much as you like and use the brakes when needed. Maximizing regen usually hurts your range. Minimizing regen (like your coasting in D) usually helps your range. Sport mode feels peppier, but it just remaps the accelerator to do more with less pressure. but mashing it to the floor in L, D or asport mode accomplishes the same thing. The car won't go any faster. Now if you got lighter wheels and tires, or smaller wheels and tires, you can imove your acceleration a little. If you shed all the weight (around your belly, plus strip out everything in the interior except the driver's seat, you will get a little enter acceleration. But the simplest way to achieve a big boost in acceleration is to trade the volt in for an ELR, CT6 Plugin, or Tesla
I wondered about this. I had tried Sport mode a few times and didn't feel any difference. When I floor the car I really do put the pedal to the metal.
 

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But I like to coast, as my traffic isn't expressly stop & go. It's not as easy to do in L.

Then just stay in D and use the brake pedal. L just increases the regeneration when off the accelerator. The car still regenerates using the brake pedal. I like using L for local stop and go and for the way it keep me from speeding up too much on downhill sections. What you're most comfortable with.
 

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I've been around and around on this and have tried extensive driving in either mode--what I don't like is shifting between L and D very often. I drive on hilly terrain pretty much exactly half of my 20 mi commute and fairly flat the rest of the way, and the rest of the time is stop-n-go in town. I like L because it gives me more control over speed--D barely feels like its slowing down to me. I think I'll get over that in time though. I don't like L because it takes more planning to come out of cruise control smoothly.

But the big deal is that you can achieve in D what you get in L. Its been said throughout this thread in a couple different ways, but to put it more bluntly, using L to save your brakes is probably not saving them much because when you press on the pedal you start engaging Regenerative Braking and you don't engage the mechanical breaks unless you brake quite hard or you are nearly stopped
 

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If you want to maximize range, use D and coast as much as possible. And if you have to hit the brakes, try to do so gently. Even this causes regen, unless you press too hard on the brake (thereby engaging friction brakes) or the speed goes below 5mph or so.

Use L if you like one-pedal driving. You can maximize range here too, but you will need to feather the accelerator pedal so as to not lose momentum unnecessarily.
 

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Discussion Starter #19
Now if you got lighter wheels and tires, or smaller wheels and tires, you can imove your acceleration a little. If you shed all the weight (around your belly, plus strip out everything in the interior except the driver's seat, you will get a little enter acceleration. But the simplest way to achieve a big boost in acceleration is to trade the volt in for an ELR, CT6 Plugin, or Tesla
I didn't post a picture of my belly, LLninja! ROFL!!!!
 

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With both Volt and ELR, I drive in 'L' except a few times in snow or bad weather. Now when I drive in 'D' it feels weird. I have no issues coming off of cruise (now ACC) when driving in 'L'.

No matter what I drive, it makes people sick when they ride with me. :) I don't spare the electrons or the gas.
 
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