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Which driving style do you use, in terms of gears: D, L or N or combination of gears?


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Discussion Starter #1
I normally drive in a combination of D, L and N, in order to optimize regen and momentum:

I use L whenever i need to slow down before a stop or a curve, getting the most efficient regen, without having to feather the brake pedal while watching the energy ball. I use D on long flats w/out stops (like freeways or expressways) and will switch into N on the descents, to take advantage of the momentum.

Obviously i could use L for all of this, as long as i was perfect in my accelerator feathering, but since that is impossible, the combination approach is more efficient.

Curious what others do.
 

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D, L

Mostly in D-Mode, L applies when approaching a traffic light or conjested roads, inner city streets or steep declines.

Besides that, I am seldomly in SPORT mode (either in D or L, especially not in L).

I wish the car had flappy paddles to switch between D, L; also I'd wish an additional regen-Mode.

Never been in N.
 

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I feather the throttle with my right foot if I want the equivalent of "D", use "L" virtually always.
 

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Mostly in L but open road freeway in D to get most coasting effect.
 

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+1, D+L+N

and here we go.
HAHA! Indeed. :p

That's the stupidest thing I've read today.
When you coast in D (without feathering the accelerator pedal), especially at higher speeds, there can be significant regen/drag that slows the car down. It converts your kinetic energy into electrical energy and then into chemical energy in the battery. Then, later, that energy stored in the battery is used to re-accelerate the car. None of these conversions are 100% efficient, so you lose some energy/efficiency in the process.

In many coasting scenarios, whether on flat terrain or downhill, it will be more efficient to coast in N to maintain your speed/momentum as much as possible rather than using regen to slow the car down, convert your kinetic energy into chemical energy, and then convert it back to kinetic energy. It's not so stupid. Basic physics/thermodynamics, really. You can essentially do the same thing by feathering the accelerator pedal in D, but it's hard to do accurately and is annoying and distracting.

Of course, there are some exceptions. If a decent is particularly long and/or steep and your speed gets too high, then the exponential increase in aerodynamic drag can outweigh the efficiency benefits just mentioned. And there are other downsides to N -- particularly the complete loss of regen when using the brake pedal. So it has to be used only when there are not likely to be any surprise stops coming up.
 

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It's stupid because its dangerous and illegal. http://www.bestattorney.com/california-motor-vehicle-code/coasting-downhill-21710.html

Every state has similar statutes.

In a fuel-injected ICE vehicle, you use more fuel since you don't get the benefit of fuel cut-out.

In *any* vehicle, driving with this 'hypermiling' crap needs to die. How much do you weigh? You'll save more fuel by losing weight than all the hypermiling you could ever do, both in the direct carriage of that weight in your vehicle and in the reduced resources required for all those unnecessary calories. You also won't endanger and annoy the hell out of everyone else on the road while doing it.
 

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It's stupid because its dangerous and illegal. http://www.bestattorney.com/california-motor-vehicle-code/coasting-downhill-21710.html

Every state has similar statutes.

In a fuel-injected ICE vehicle, you use more fuel since you don't get the benefit of fuel cut-out.

In *any* vehicle, driving with this 'hypermiling' crap needs to die. <snip> You also won't endanger and annoy the hell out of everyone else on the road while doing it.
Here, here!! Two thumbs up!!!
 

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I have never driven downgrade that a car in neutral did not speed up requiring braking to keep the speed even. Even in D on descents more than 2-3% I need to keep my foot on the brake to keep the speed even.

I have seen people who just allow the car to accelerate to whatever speed it makes in neutral going downhill in order to recoup it on any subsequent incline and I have also seen them have to hit the brakes when someone pulls in front of them if, for no other reason than they are doing 90 in a 70 zone. You can tell because they don't pass the car that was, or was not, in front of them in the other lane. Or, because they are being nice and know the CHP likes to sit at the bottom of long declines catching drivers who do it.
 

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It's stupid because its dangerous and illegal. http://www.bestattorney.com/california-motor-vehicle-code/coasting-downhill-21710.html

Every state has similar statutes.

In a fuel-injected ICE vehicle, you use more fuel since you don't get the benefit of fuel cut-out.

In *any* vehicle, driving with this 'hypermiling' crap needs to die. How much do you weigh? You'll save more fuel by losing weight than all the hypermiling you could ever do, both in the direct carriage of that weight in your vehicle and in the reduced resources required for all those unnecessary calories. You also won't endanger and annoy the hell out of everyone else on the road while doing it.
Part of the rationale does not seem to apply to an EV. I do this frequently in my neighborhood that has some small hills. This allows me to maintain a speed around 25 mph or so. If I did not shift into N, I would be accelerating more on the inclines. This saves me 0.1 - 0.2 kWh leaving my neighborhood.

I never take my foot away from the accelerator and I do not see why this is really dangerous as long as one does not coast faster than speed limit.
 

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Discussion Starter #13
+1, D+L+N


When you coast in D (without feathering the accelerator pedal), especially at higher speeds, there can be significant regen/drag that slows the car down. It converts your kinetic energy into electrical energy and then into chemical energy in the battery. Then, later, that energy stored in the battery is used to re-accelerate the car. None of these conversions are 100% efficient, so you lose some energy/efficiency in the process.
.
Exactly. Glad i didn't have to explain the obvious.
 

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I'd really love to know how many of the D-L-N drivers (3 so far) come from driving a Prius.

The only people I know that do this crazy stuff are Prius owners. Who else would screw around with their shifter all the time--while endangering everyone else--just to save a few pennies (maybe) of gas??? It's just nutty, in my humble opinion.
 

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Yes. Here we go again. LOL I bought the Volt with money that I saved hypermiling over the last 9 years. Don't bash what you don't understand. How does $10,000 in savings in fuel cost over 3 years sound? That's what I saved in fuel when I switched to a fuel efficient vehicle and hypermiling versus the Nissan truck I was driving 30,000 miles a year.
 

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Or just drive a Volt...:rolleyes:
 

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Discussion Starter #17 (Edited)
I'd really love to know how many of the D-L-N drivers (3 so far) come from driving a Prius.

The only people I know that do this crazy stuff are Prius owners. Who else would screw around with their shifter all the time--while endangering everyone else--just to save a few pennies (maybe) of gas??? It's just nutty, in my humble opinion.
Looks like JUST as many people "screw around with the shifter all the time" as do the ones that stay in L and are constantly "screwing around with the accelerator". Add together the D+L with the D+L+N and you get 18, just like the L only.

It has nothing to do with the prius. I have never and would never go near a prius.

Shifting the volt between the gears is NO more dangerous than driving a manual, where EVERYONE "screws around with the shifter" ALL the time. I have driven manual transmission most of life, and am very comfortable "screwing around with shifter", without any loss of safety.

Now, in terms of this OTHER supposed loss of safety, let's look at the site that you guys are pointing to:

http://www.bestattorney.com/californ...ill-21710.html

It has 5 points saying how BAD driving in neutral is:

2. Engine could die in neutral.
- Doesn't apply to the volt.

3. Brakes burn up faster on downgrades.
- Doesn't apply to volt. Just shift into L and use up some of the speed to regen, if speed gets too high.

4. Coasting will not save gas (electrons).
- Clearly it will.

5. Removal of feet from pedals.
- Yes, removal of feet from the pedals is not safe. So, don't do it. Doesn't mean you can't use N.

1. Better control of the vehicle.
- Left this to last, since it seems to be the most contentious. Better control of your vehicle how?
a) Because in gear, the gear will slow you a bit, and thus your speed won't cause you to lose control. Well, you can use the brakes the same way, as necessary.
b) Because in gear, you can accelerate. Well, you can easily shift into gear to accelerate as necessary. Is it as quick? Well, i posit that you will often have your foot on the brake if coasting down a hill, so in the time you could move your foot from the brake to the accelerator, you can also shift into D, concurrently with no loss of time.
 

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Hi ScotMac--

First off, I have no issue at all with folks who select D or L for different driving conditions (e.g, highway versus city). Always L is my preference, but I understand that others prefer D sometimes. I doubt that too many of those folks are screwing around with their shifter all the time, though, like your D-L-N technique espouses. (By the way, almost all of my prior cars have been sports sedans with manual transmissions. They are very fun to drive. That said, while I have tried it, I've never enjoyed similarly shifting an automatic transmission for fun or for any other reason.)

Here are two interesting threads on Driving in N:

http://gm-volt.com/forum/showthread.php?15853-Regen-in-quot-N-quot-and-quot-D-quot-Interesting-Observation
http://gm-volt.com/forum/showthread.php?10624-Just-a-Review-For-My-Sanity-Driving-in-quot-L-quot&p=107329#post107329

Note that if you really are attempting to save every penny, certainly you are unwise to hit the brake pedal in N. You will end up heating the brake pads and getting absolutely zero regeneration.

I hope that you don't wear out your shifter. To each their own, I guess...
 

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Looks like JUST as many people "screw around with the shifter all the time" as do the ones that stay in L and are constantly "screwing around with the accelerator". Add together the D+L with the D+L+N and you get 18, just like the L only.
I have stayed away from this thread, but sorry, that just makes no sense. Some things are designed for continuous use and others are not. Equating the two is naive.

For sure, to each its own, but trying to re-create arbitrary scenarios that 'prove' that some elaborate scheme designed to save a miniscule amount of whatever is as convenient or as safe as standard operating procedures is bordering on irresponsible.

And don't forget what's next after N while you are pushing the shifter forward in order to save a fraction of a penny. And then we wonder why sometimes manufactures go into such extremes to protect us from ourselves.
 

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I saved in fuel when I switched to a fuel efficient vehicle ... versus the Nissan truck I was driving 30,000 miles a year.

Fixed. You didn't save $10k by hypermiling, you switched to a more efficient vehicle. Without data for the truck, the more efficient vehicle, and the hypermiling independently, you cannot claim how much it saved.
 
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