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Discussion Starter #1
In Low gear I noticed much more regenerative braking, and the owner's manual makes no mention about harming the Volt this way. It's so damn cool: you can be driving at 60+ MPH, shift to low and the car gently coasts until you touch the brake, THEN you get the dramatic braking effect, all the way down to 1-2 MPH. Fantastic!
So, if shifting to Sport Mode and driving in Low, you get this very lively sporty perky responsive experience. You gotta try it!
I don't think the Volt actually shifts any gears when Low is selected; it feels all electronic. Am I right?
M
 

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There's no gears, "L" is all electronic and basically gives the Volt maximum slowing power without using the brakes, i.e. maximum regen. I love how they mapped the gas pedal too; in this mode, if you're only slightly on the gas pedal, it equates to less regen, but not acceleration. Makes for a very smooth ride once you get used to it.

For the most part I've been using "L" around the city with a lot of stop and go, and "D" on the highways, unless I see somewhere ahead that I'll need to slow down more than normal.

The "L" feeling at any speed is defintely cool. With Sport mode and "L", the Volt feels like a very sporty vehicle.
 

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In Low gear I noticed much more regenerative braking, and the owner's manual makes no mention about harming the Volt this way. It's so damn cool: you can be driving at 60+ MPH, shift to low and the car gently coasts until you touch the brake, THEN you get the dramatic braking effect, all the way down to 1-2 MPH. Fantastic!
So, if shifting to Sport Mode and driving in Low, you get this very lively sporty perky responsive experience. You gotta try it!
I don't think the Volt actually shifts any gears when Low is selected; it feels all electronic. Am I right?
M
You are right. I drive mostly in Normal-L to maximixe my E-range. I learned quiclky how to feather the throttle when slowing so as not to "jerk" my passengers.

As I understand the transmission, the traction motor only shifts gears when running at speeds over 70mph. So if driving at speeds under 70, there is no shifting gears and any combination of Normal, Sport, Mountain, D or L can safely be used.

I like Sport-L when driving local roads and I'm not concerned for E-Range. For maximum E-Range, I drive in Normal-L to cushion my starts and regen as much as possible. On the highway, I use Normal-D. GM has done a great job giving us all these options. The Volt is a blast to drive and folks keep stopping me to ask about it. How cool is that?

VIN63
 

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Discussion Starter #7
Many thanks to all responders. Low is amazing! And of course thanks to GM. A marvelous result of American enginuity.

Marv
 

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90-95% L use, but I still get a weird feeling I am going to blow out the transmission driving in L. After driving regular transmissions for 35 years, it is hard to reprogram your brain. Now if I could only stop trying to remove a non-existent key out of the steering column when I get out of the Volt:)
 

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I had been driving around town in Normal - D, but after reading this will see what difference going to Normal - L does in around town...that sweet SPORT mode is the best for showing off "BSD", but definitely culls a bit off the range. Have you guys noticed a difference between the - D and - L in Normal driving? I'll test it out myself as well....had been getting about 39 MPC with the Normal - D with downshifting to L when stopping (did this all the time with my Escape Hybrid).
 

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Reading previous topics about "L" before driving the Volt encouraged me to try it. I was overjoyed at how well it works. It's as if you have carefully downshifted so you only have to press the brake for a short distance. Watch the car ahead, because you still need the friction brake. The brake travel requires a bit more distance to activate the friction brake, be careful and make sure you have fully pressed the brake pedal to stop the Volt.

It reminds me of the single pedal Disney Autopia cars. The announcer says, "To make your car go, push down on the pedal. To stop, take your foot off the pedal." One big difference, the friction brake is NOT applied in the Volt when you take your foot off the (accelerator) pedal.

http://www.themeparkaudioarchives.com/members/disneyland_tomorrowland.html - Autopia Safety Spiel

What I appreciate about "L" is how it takes the guess work out of regenerative braking. You know that when you lift your foot off the accelerator, maximum regeneration occurs. It helps you stop faster too, because in that split second to get your foot on the brake, the Volt is slowing down. Where it doesn't work is when you want the Volt to act like an ICE vehicle when you stop accelerating. That is why "D" is perfect for those open roads.

Pure perfection in motion equals award winning performance.

(Limitations of regenerative braking with EV-1 reference: http://en.wikipedia.org/wiki/Regenerative_brake#Limitations )
 

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In my Prius, the regenerative braking triggers the brake lights at a certain points. Under heavy "L" regenerative deceleration does the volt trigger the brake lights? I would think all of this heavy deceleration might lead to some issues there. Also, if you hit a bump, pothole, or slick spot when just regenerative braking with the front two wheels, is there a brake-loss sensation? I am used to it from priuses dating back to 02, but I know it made a huge uproar on the prius forums. I compared it to downshifting in my bmw. You get the same braking loss sensation if your relying on engine braking over 4-wheel friction brakes.

I cannot wait to get my volt and find all this out first hand!
 

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Where it doesn't work is when you want the Volt to act like an ICE vehicle when you stop accelerating.
I'd add "if you want the volt to feel like an ICE vehicle with an automatic transmission when you stop accelerating. Take a stick shift car, get up to 6000RPM in 1st gear and suddenly let go of the gas; you'll be slowing down real quick ;)

The Volt in L will be similar to how I drive my current manual transmission car when coming down an offramp of similar situation, downshifting through the gears to slow down and only using the brakes once I'm down to 10-15 mph.
 

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Maximum regen is about 60kW. Do you guys really think it's recovering that much power? I would expect L to be calibrated to a "moderate engine braking deceleration" level, but not necessarily the full 60kW. Do we have any official answers?

By my (very rough) calculations, 60kW would decelerate the Volt from 60mph to 10mph in about 6.3 seconds. This assumes a frictionless plane, with no energy loss to capture the power. But while the aero and friction losses would actually increase the deceleration rate, the inefficiency of capturing the energy through the motor would offset that. So how close to my estimate does the Volt decelerate in L?
 

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I love "L" mode. I live on top of a mountain, so I leave my house fully charged (indicator shows 40 miles battery range available). I ride down the mountain in "L", never really needing to hit the brakes the way I do in my truck. By the time I get to the bottom of the mountain, it shows about 47 miles avilable in the battery!
 

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I love "L" mode. I live on top of a mountain, so I leave my house fully charged (indicator shows 40 miles battery range available). I ride down the mountain in "L", never really needing to hit the brakes the way I do in my truck. By the time I get to the bottom of the mountain, it shows about 47 miles avilable in the battery!
That's really good! Just a guess but that means that you store away about 2.1 KW into the battery!
 

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But if my battery was already "fully charged", how can it now be holding more?
Sorry miss calculated and corrected post... 2.1 KW is the right answer. As to storage, remember the battery only charges to 80% of capacity and also, you may use some energy if the mountain grade is some distance from your house. Just a guess as I do not know the lay of the land by your home.

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That's why the battery only charges to 80% (or whatever the number is now, since they opened up the battery usage to 65%). So that people could do what chemdawg did, the "head room" is for additional charge from regen.
 

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The headroom is actually mainly for battery longevity. These types of batteries degrade when you charge or discharge them all the way. I suspect they opened up the amount we can use because they weren't hitting the mpc rating they wanted.

My LenovoT60 laptop has a similar feature that can be enabled to not charge the battery all the way to 100%. Instead it charges to about 97-98% for battery longevity.
 
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