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Discussion Starter #1 (Edited)
A few months ago idleup published a few controversial threads that all got closed. Still, I was curious and tried to do V----ing to see if it could indeed gain range using mountains mode. But back in Feb, it was cold and I had horrible results. Over the past few days, my daughter had several out of town track meets (she got 1st place at conference, but 6th in sectionals) which gave me the perfect conditions to try v---ing again in warmer weather. It still doesn't work. At 60 mph, 65 mph, or 70 mph the battery miles generated just don't cause the MPG number to move anywhere above my normal 35-38 mpg. When using ice, the trip odometer would show 18-22 mpg when doing the mountain mode run, then start to climb to around 35-38 mpg as I deplete the battery and I return to mountain mode.

Temps were between 65-75 degrees. Next test will be this summer under ideal EV conditions
 

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I am doing many more long range trips now, and have good data for the "let the volt do its thing" method... I may loose my mind and try V....ing on one of the trips just for my own data set.

I still wish Voltamorting worked on days other than April 1st!

Keith
 

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A few months ago idleup published a few controversial threads that all got closed. Still, I was curious and tried to do V----ing to see if it could indeed gain range using mountains mode. But back in Feb, it was cold and I had horrible results. Over the past few days, my daughter had several out of town track meets (she got 1st place at conference, but 6th in sectionals) which gave me the perfect conditions to try v---ing again in warmer weather. It still doesn't work. At 60 mph, 65 mph, or 70 mph the battery miles generated just don't cause the MPG number to move anywhere above my normal 35-38 mpg. When using ice, the trip odometer would show 18-22 mpg when doing the mountain mode run, then start to climb to around 35-38 mpg as I deplete the battery and I return to mountain mode.

Temps were between 65-75 degrees. Next test will be this summer under ideal EV conditions
From my experience, you can truly game how many electric miles your car will show on very long trips. My Volt is a 2012. Here is how to do it. Don't let the car fully use the battery at any time. Start out in MM and use the battery down to where the engine starts to be used. Then, at opportune times, switch between MM and normal. For example, when going down long hills, switch to normal and don't use MM. Do this at other times when you know the car will coast. It is a lot of fun and you can eek out many miles out of the battery. Use what you think you gained coasting in normal, then switch back to MM. For example, it is not uncommon for me to show 75 miles out of the battery only when messing around like this; HOWEVER, it is all a wash. I will still use the same amount of fuel over my trip. It is fun to see so many battery miles though, but it does not save me any fuel. I have done this many times when we go to Dollywood (amusement park in Tennessee), and for us, Dollywood is about 300 miles round trip. Playing around like this does not help or hurt fuel economy when done correctly, but it is fun, and adds many miles to the electric total.
 

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Discussion Starter #5
From my experience, you can truly game how many electric miles your car will show on very long trips. My Volt is a 2012. Here is how to do it. Don't let the car fully use the battery at any time. Start out in MM and use the battery down to where the engine starts to be used. Then, at opportune times, switch between MM and normal. For example, when going down long hills, switch to normal and don't use MM. Do this at other times when you know the car will coast. It is a lot of fun and you can eek out many miles out of the battery. Use what you think you gained coasting in normal, then switch back to MM. For example, it is not uncommon for me to show 75 miles out of the battery only when messing around like this; HOWEVER, it is all a wash. I will still use the same amount of fuel over my trip. It is fun to see so many battery miles though, but it does not save me any fuel. I have done this many times when we go to Dollywood (amusement park in Tennessee), and for us, Dollywood is about 300 miles round trip. Playing around like this does not help or hurt fuel economy when done correctly, but it is fun, and adds many miles to the electric total.
Well, flat Illinois has no hills. I really don't have any interest in causing the EV numbers to show an insane level, just trying to see if V----ing actually can gain a few MPG. But I'm finding the same thing as you, it doesn't make any difference in actual MPG. I actually let the battery get down to zero, then grow back to halfway, and it all gets counted as ice miles. The MPG on the trip odometer is what I'm using to gauge whether this works or not.
 

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Discussion Starter #6

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I think the only plausible way for MM to help efficiency is if it indeed allows deeper dips than hold, without revving up.
i.e. up a hill it keeps the revs locked and uses battery to boost (and recharges on the way down) whereas in hold it would up the revs to max
I will test this one on the next cottage run (tons of hills along the way).
But starting and stopping doesn't seem any more useful in my mind, and I'm really not surprised at your findings.

tldr;
IBTL
 

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Life is complicated enough, so when I drive there are two numbers of interest that I can compute from information provided by the Volt – miles/kWh (electric) and mpg (gas). My goal is to maximize both these values without trying to spend too much time playing with the buttons and not hypermiling. However, if there is something to gain by V----ing, then perhaps I will try it, but will let you guys do the testing/confirmation.
 

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Discussion Starter #9
I think the only plausible way for MM to help efficiency is if it indeed allows deeper dips than hold, without revving up.
i.e. up a hill it keeps the revs locked and uses battery to boost (and recharges on the way down) whereas in hold it would up the revs to max
I will test this one on the next cottage run (tons of hills along the way).
But starting and stopping doesn't seem any more useful in my mind, and I'm really not surprised at your findings.

tldr;
IBTL
So maybe the fact I have no hills is causing V---ing to not work for me. IL is soooo flat.

I've wondered fro quite some time whether a hold+ mode might be useful, where the ICE does what it does in hold mode, but when you do some regen, it stores it rather than uses it to take you back to the level before your pressed hold. Better yet, it uses just a bit more ICE to generate just a little more electricity to fill the battery. It would be nice to drive 300 miles and slowly fill your battery back all the way to 100% on the guessometer.
 

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So maybe the fact I have no hills is causing V---ing to not work for me. IL is soooo flat.

I've wondered fro quite some time whether a hold+ mode might be useful, where the ICE does what it does in hold mode, but when you do some regen, it stores it rather than uses it to take you back to the level before your pressed hold. Better yet, it uses just a bit more ICE to generate just a little more electricity to fill the battery. It would be nice to drive 300 miles and slowly fill your battery back all the way to 100% on the guessometer.
You need signs like this...:)
 

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It looks like basic physics. In simple terms there's no such thing as a free lunch. My theory is the best gas mileage for road trips all else being equal, is to use hold mode with 50% or better battery charge. My experience has been my mpg has exceeded that reported while V---ing.
 

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From my experience, you can truly game how many electric miles your car will show on very long trips. My Volt is a 2012. Here is how to do it. Don't let the car fully use the battery at any time. Start out in MM and use the battery down to where the engine starts to be used. Then, at opportune times, switch between MM and normal. For example, when going down long hills, switch to normal and don't use MM. Do this at other times when you know the car will coast. It is a lot of fun and you can eek out many miles out of the battery. Use what you think you gained coasting in normal, then switch back to MM. For example, it is not uncommon for me to show 75 miles out of the battery only when messing around like this.
The 2011/2012 Volts had a programming glitch that resulted in the counting of MM-recharged battery miles as electric miles if you switched to MM before the battery was fully depleted, allowed the system to recharge your battery, then switched back to Normal mode.

What you might not have noticed is that the kWh Used number did not start increasing again until you drove some distance down the road (i.e., not until the battery soc had dropped to where it was when you switched to MM).
 

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It is unclear if MM is anything more than a variant of Hold mode where the computer, not the driver, selects the battery soc to be "held." Is there any technical documentation available that even suggests the propulsion system operates differently in MM than in Hold mode at that approximate soc? If Hold mode had been available in the 2011/2012 Volts, would there have been any need for MM? Could the manual have stated: "Driving in Mountains: Select Hold mode when at least 4 bars of power are still available, or stop to recharge, before driving up mountainous roads, to avoid degraded performance."

Mountain Mode is designed to "reserve" a specific amount of battery power for use in case additional power is needed under high-power-demand conditions, such as driving up steep roads (hence: "Mountain" mode). The ability to charge a depleted battery back up to the MM-maintained soc, if needed, instead of requiring the driver to stop and plug into the grid to recharge, is a "feature" of MM, not its purpose, and cannot be turned off by the driver.

The time frame and extra gas needed to recharge the battery using MM seem to be independent of the speed of the car (say, when driving on level ground). Perhaps one should just drive fast when MM is recharging (i.e., run up as many miles as possible during the short amount of trip duration when gas is actually being used) any then drive slow while using this recharged battery power (i.e., driving slow increases the distance you can drive on that amount of recharged power, increasing the Gas Miles total number for the MPGcs calculations, and the slow speed increases the percentage of driving time when the ICE is not running).
 

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Discussion Starter #14 (Edited)
You know, all these games would become moot if GM just gave us an optional battery expansion pack to achieve 100 miles of Ev range. I would drive it like I stole it every day and not worry about losing a little range since I have more than enough to make my 50 mile round trip without hitting the Dino juice. Tesla has been selling multiple battery sizes for years, why won't GM? Even the bolt can be outfitted with an economy and an XL battery for those who just want to push there cars to eleven.

http://youtu.be/uMSV4OteqBE
 

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The 2011/2012 Volts had a programming glitch that resulted in the counting of MM-recharged battery miles as electric miles if you switched to MM before the battery was fully depleted, allowed the system to recharge your battery, then switched back to Normal mode.

What you might not have noticed is that the kWh Used number did not start increasing again until you drove some distance down the road (i.e., not until the battery soc had dropped to where it was when you switched to MM).
You are 100% correct in what you state, and in reality it doesn't really matter how the Volt counts the miles. What matters is how much gas you use in total no matter how the kWh meters counts it. I have driven that "DollyWood" trip many, many times as we always get season passes and the kids love it. No matter how I try to game the system I always use about the same amount of gas which is usually spot on about 5.5 gallons if we don't make any side runs. This is whether my Volt shows 40 miles electric or 75 miles electric on the 300 mile trip. I still use the same amount of gas ;)

Note, this is not driving on the highway, this is driving on rural mountain roads which is much more fun in the Volt :)
 

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. Tesla has been selling multiple battery sizes for years, why won't GM?
I can think of several reasons why GM did not offer the option of different energy batteries. First, the Volt is a PHEV and not a BEV. If you need more range, use gas and the oil industry will thank you and GM. Second, GM is an old entrenched, legacy auto company that was bailed out by the taxpayers. They didn’t want to add more financial risk to the Volt by offering battery options. Third, they are not based in Silicon Valley where “thinking outside the box” and risk-taking are the norm. So if its new/novel, then its worth considering.
 

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It is unclear if MM is anything more than a variant of Hold mode where the computer, not the driver, selects the battery soc to be "held."
Or, keeping with the timeline as introduced, Hold is nothing but MM with a flexible set point and a REALLY clumsy method of setting that point. I mean, if you could actually dial in the number of bars you wanted Hold to sit at, that'd make MM essentially moot. As it is, there's no way to tell Hold Mode "I want 40% reserve" if you're at 20% already.

Unless you kick it into MM, that is. Kind of out of luck if you want 60% or something, though.
 

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You know, all these games would become moot if GM just gave us an optional battery expansion pack to achieve 100 miles of Ev range. I would drive it like I stole it every day and not worry about losing a little range since I have more than enough to make my 50 mile round trip without hitting the Dino juice. Tesla has been selling multiple battery sizes for years, why won't GM? Even the bolt can be outfitted with an economy and an XL battery for those who just want to push there cars to eleven.

http://youtu.be/uMSV4OteqBE
And this additional battery would go where exactly? GM didn't leave much space open, and what they did is mostly needed for crash safety or passengers/cargo.

Like the rest of the industry, GM is using lower density cells of larger format than Tesla, so getting that kind of range isn't trivial... 100 EPA miles means ~30 kWh of usable battery, which means GM would need at least 36 kWh and probably 48 to keep the degradation under control. Since the current 16 kWh pack is 435 pounds, that's an 800-1200 pound battery pack - which of course makes the car slower and reduces efficiency even if you had a place to put it. (Note that the Tesla 85 kWh pack is about 1300 pounds - thanks to the previously mentioned higher energy, more dangerous chemistry in cylindrical cells.)

GM played a bunch of tradeoffs and built the best car they could under them. Tesla took a different, more aggressive route, and built what is probably a better car - that costs a whole lot more money to make (and sells for a lot more money, too.)

GM couldn't emulate Tesla without incurring the costs and risks Tesla did...
 

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I can think of several reasons why GM did not offer the option of different energy batteries. First, the Volt is a PHEV and not a BEV. If you need more range, use gas and the oil industry will thank you and GM. Second, GM is an old entrenched, legacy auto company that was bailed out by the taxpayers. They didn’t want to add more financial risk to the Volt by offering battery options. Third, they are not based in Silicon Valley where “thinking outside the box” and risk-taking are the norm. So if its new/novel, then its worth considering.
Or maybe the increased range is more critical in a BEV because when you run out of charge the car stops moving.
 
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