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Discussion Starter · #1 · (Edited)
For the total Eclipse my wife and I drove from southwest Denver, CO to Lincoln, NE and then over to Broken Bow, NE before returning home. EV range was better than expected – ICE didn’t come on until Hudson, CO, which was about 10 miles past where I anticipated. All driving was done in “Normal” mode.

When I ran out of battery I was headed up a long hill at 80 MPH and it took nearly a mile for the ICE engine to fully take the load. The initial cut over was quick but the power meter didn’t really show the power transfer for close to a minute after the console made the shift from battery to ICE.

As far as I can tell the 75 MPH speed limits on I-76 and I-80 are actually minimum speed limits. At 80 MPH I was passing about as many cars as were passing me and most of the passes were no more than 1-2 MPH speed differentials so that’s obviously the driver selected target speed for both roads. Using this as a starting speed my Volt was very responsive when I needed to accelerate to pass someone sitting and not passing (illegal in both states) in the left lane. My Volt easily accelerated to over 90 MPH running on ICE for these passes and then dropped back just as quickly to the set speed.

When asked for power even with the batteries depleted, the car would pull from battery first. What I hadn’t noticed back in June when I drove to New Hampshire (car was still too new for some details) is that when running on ICE the Classic Enhanced display shows power from battery and ICE. During steady state driving the ICE meter shows power but the battery meter is zero’d. When you request power you can see the car pulling from the batteries first as the battery power meter will soar and then come back down as the ICE meter raises. After doing this the ICE meter (and engine volume) remains "high" for a short period of time while the battery meter actually goes negative. I’m assuming this is the car putting that used charge back into the batteries. While the flow meter would show ICE charging I never actually noticed the ICE revving just to charge the batteries while driving steady state on relatively flat ground.

When reentering the interstate from a rest area or side road on-ramp I had more than sufficient power to accelerate to 80 MPH prior to actually having to enter the travel lanes. Except for the first acceleration on Monday morning these were all done on ICE. Yes, the ICE engine “screams” but even at its loudest it’s quieter than almost every other car on the road. The pattern of battery providing power first followed by ICE combined with a short recharge period held true here as well.

Through rural Nebraska I ran on cruise control set at the posted speed limit of 60 or 65 mph, depending on the road. East of Broken Bow it was rather flat. West of Broken Bow it got hilly and I shifted to L to ensure I didn’t pick up speed going downhill. There were several speed traps on these roads and my Volt never wavered more than +/-1 MPH from the cruise set speed driving through these hills.

On the way back we drove through three construction related traffic jams resulting in single digit speeds. Remember, I have no battery charge available for this. What I noticed was the car running ICE to charge the battery a little and then turning ICE off. This ran in cycles lasting about five minutes each – 30 to 60 seconds of ICE and then the remainder of the cycle on battery.

Finally, when I stopped in Lincoln I asked if I could plug my car in for the night. The owner of the hotel said he didn’t have any 240v outlets. Once I explained I could use 120v he had no problems. I found a 20amp outlet between two A/C compressor units and based on the outlet construction switched to 12-amp charging. My car didn’t charge fully simply because it was plugged in for only about 11 hours. Also, when I got home I only had about 9 hours to charge. When I left for work yesterday the charge information screen was hopelessly confused after two partial charges but reset after completing a full charge. My overall mpg for the 1,040-mile trip was 42 (EV & ICE) while my ICE mpg was 37.6. I found a Shell station in western Nebraska and arrive home with 110 miles left on the gas tank (one-third of a tank), right where I want to keep the car for normal daily driving. The EV range guess-o-meter is sensitive to ICE driving patterns. If your recent ICE mpg is low the first full battery charge will reflect this. My car showed only 52 miles of battery range after the first full charge but I still ended up with the 60 mile range that I have come to expect during my daily commute.
 

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I'm surprised you took the entire trip in Normal mode. I would think when leaving Denver you should be in Mountain Mode until you get to the Great Plains.
 

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Discussion Starter · #5 · (Edited)
FYI, the reason the car is slow to transfer the load from battery to ICE is because the ICE is allowed to warm up at low RPM before taking load.
I knew that. But it was kind of interesting to see how long it actually took. I've had my car switch to ICE at lower speeds and the transition is a lot faster. I also suspect, based on the flow diagram, that the ICE engine isn't actually turned off when the car goes into electric only regeneration. Instead I think the ICE engine goes into Deceleration Fuel Cut-Off (DFCO) where the fuel injectors are turned off and the drive wheel spin is transmitted back via the transmission to the engine to keep it turning. Restart is too quick for a full shutdown.
 

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Discussion Starter · #6 · (Edited)
I'm surprised you took the entire trip in Normal mode. I would think when leaving Denver you should be in Mountain Mode until you get to the Great Plains.
Denver is actually on the plains. I live at the base of the first range of serious hills to the west of Denver. I did consider hold mode for the trip back as there is a high speed (80 mph) climb of about 2,500 feet as you leave Nebraska back to my home, but after watching the car's behavior on the way out I decided to stay in normal mode. I'll probably only use Hold mode if I head west into the mountains and know I won't have enough battery. I live at 5,700 ft above sea level.
 

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Denver is actually on the plains. I live at the base of the first range of serious hills to the west of Denver. I did consider hold mode for the trip back as there is a high speed (80 mph) climb of about 2,500 feet as you leave Nebraska back to my home, but after watching the car's behavior on the way out I decided to stay in normal mode. I'll probably only use Hold mode if I head west into the mountains and know I won't have enough battery. I live at 5,700 ft above sea level.
Mountain Mode for going west.
 

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Discussion Starter · #8 ·

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My wife and I just completed our first 1000 mile trip in our 2017 Volt. We were towing a small aluminum trailer with two kayaks and two paddleboards. We climbed from sea level to over 5200 ft. both going and coming. Our trip was from Belfair, WA via Yakima to Joseph, Oregon. We knew we would not have access to charging at our destination, so I used "hold" mode most of the time. We did use some electric power while running around in Joseph and we actually started our return trip with more ev range than we had when we arrived! (I always love that). Temps were in the high 80's to low 90's and we did use the AC in eco mode some of the time. Our overall mileage was about 37mpg. The aero drag from the trailer as well as the elevation changes were clearly a factor, but still we were more than pleased with the performance and economy. Not afraid to take trips in this car!
 

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When reentering the interstate from a rest area or side road on-ramp I had more than sufficient power to accelerate to 80 MPH prior to actually having to enter the travel lanes. Except for the first acceleration on Monday morning these were all done on ICE. Yes, the ICE engine “screams” but even at its loudest it’s quieter than almost every other car on the road. The pattern of battery providing power first followed by ICE combined with a short recharge period held true here as well.
I also just finished my first long trip -- about 500 miles through PA. I was in Hold mode most of the time to save battery for non-highway needs, and finished my trip with about 10 miles of EV range left. I have no idea what you are talking about when it comes to noise. I thought the engine was buzzy at best. While cruising it was relatively composed, but any strain put on the engine makes it nearly intolerable. Now maybe part of that assessment has to do with getting used to silent EV driving, but I still felt the noise level of the engine under load is much worse than just about any car I've driven. Having said that, driving on the highway in EV mode is very nice -- makes me think I want a Tesla.

Other thoughts from the long trip: While I wasn't originally that happy with the seats, they proved to be very comfortable over a long haul. Yet there is a little too much hard plastic around the driver for long-term comfort. No matter where you lay your knees, they are hitting something hard. There also proved to be plenty of room for three people's luggage, and an assortment of other things. I averaged about 48 mpg in Hold mode.

And then of course there is the constant backfiring when starting in Hold mode -- but that's another topic :)
 

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I do remember a couple of times when I thought the engine was revving pretty high during a fairly steep climb. But most of the time the engine was very smooth and quiet. But I must also say that I can't wait until a car similar to the Volt can make this same trip for me without any need for a gas engine and that added complexity. The Tesla M3 may fit the bill, but I think an all electric version of the Volt would also be awesome. I like the Bolt too, but prefer the styling and comfort and features (ACC) of the Volt.
 

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I should also mention that I always monitor coolant temp when running in "hold" mode and we saw temps as high as 217 which seemed ok for the outside temps and the hill climbing. I would not be comfortable if the coolant temp got past 220...but it never did.
Also, the AC worked great too.
 

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When asked for power even with the batteries depleted, the car would pull from battery first. What I hadn’t noticed back in June when I drove to New Hampshire (car was still too new for some details) is that when running on ICE the Classic Enhanced display shows power from battery and ICE. During steady state driving the ICE meter shows power but the battery meter is zero’d. When you request power you can see the car pulling from the batteries first as the battery power meter will soar and then come back down as the ICE meter raises. After doing this the ICE meter (and engine volume) remains "high" for a short period of time while the battery meter actually goes negative. I’m assuming this is the car putting that used charge back into the batteries. While the flow meter would show ICE charging I never actually noticed the ICE revving just to charge the batteries while driving steady state on relatively flat ground.
Glad you were able to take the trip. Sounds fun!

Just to be clear, in the simplest terms the Volt delivers power from the battery to the electric motor as the sole means of propulsion. Once the extra battery capacity is used, the computer controls the ICE to generate electrical charge to replace any expended energy from the always present battery buffer. When in stop and go traffic, or after a long deceleration, the ICE only runs intermittently to keep the buffer topped-off. At highway speeds, the ICE will find an equilibrium and stay at a constant RPM, even with small variances in terrain or speed.

Th battery gauge you see is only available battery, not total battery capacity. Beyond the buffer, the Volt also reserves some capacity that is never used to maintain the health of the battery.

In more complicated terms, the ICE will couple with the electric motor to assist in forward propulsion at speeds above 50 MPH or so. The planetary transmission is a work of art, but complex to understand. Technically, the ICE does deliver power to the wheels in some situations, but in principal, it's primary job is regeneration of electricity alone. This coupling is why many users will select HOLD mode when on the highway.

It takes a while, but your mind will eventually disconnect the sound of the engine running with forward momentum.

 

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I do remember a couple of times when I thought the engine was revving pretty high during a fairly steep climb. But most of the time the engine was very smooth and quiet. But I must also say that I can't wait until a car similar to the Volt can make this same trip for me without any need for a gas engine and that added complexity. The Tesla M3 may fit the bill, but I think an all electric version of the Volt would also be awesome. I like the Bolt too, but prefer the styling and comfort and features (ACC) of the Volt.
Thumbs up!
 

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Glad you were able to take the trip. Sounds fun!

Just to be clear, in the simplest terms the Volt delivers power from the battery to the electric motor as the sole means of propulsion. Once the extra battery capacity is used, the computer controls the ICE to generate electrical charge to replace any expended energy from the always present battery buffer. When in stop and go traffic, or after a long deceleration, the ICE only runs intermittently to keep the buffer topped-off. At highway speeds, the ICE will find an equilibrium and stay at a constant RPM, even with small variances in terrain or speed.

Th battery gauge you see is only available battery, not total battery capacity. Beyond the buffer, the Volt also reserves some capacity that is never used to maintain the health of the battery.

In more complicated terms, the ICE will couple with the electric motor to assist in forward propulsion at speeds above 50 MPH or so. The planetary transmission is a work of art, but complex to understand. Technically, the ICE does deliver power to the wheels in some situations, but in principal, it's primary job is regeneration of electricity alone. This coupling is why many users will select HOLD mode when on the highway.

It takes a while, but your mind will eventually disconnect the sound of the engine running with forward momentum.

That's the Gen 1 model. For Gen 2 the engine does plenty of work in Hold mode all by itself to propel the car.
 

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Glad you were able to take the trip. Sounds fun!

Just to be clear, in the simplest terms the Volt delivers power from the battery to the electric motor as the sole means of propulsion. Once the extra battery capacity is used, the computer controls the ICE to generate electrical charge to replace any expended energy from the always present battery buffer. When in stop and go traffic, or after a long deceleration, the ICE only runs intermittently to keep the buffer topped-off. At highway speeds, the ICE will find an equilibrium and stay at a constant RPM, even with small variances in terrain or speed.

Th battery gauge you see is only available battery, not total battery capacity. Beyond the buffer, the Volt also reserves some capacity that is never used to maintain the health of the battery.

In more complicated terms, the ICE will couple with the electric motor to assist in forward propulsion at speeds above 50 MPH or so. The planetary transmission is a work of art, but complex to understand. Technically, the ICE does deliver power to the wheels in some situations, but in principal, it's primary job is regeneration of electricity alone. This coupling is why many users will select HOLD mode when on the highway.

It takes a while, but your mind will eventually disconnect the sound of the engine running with forward momentum.

OP has a gen2, which couples the engine to wheels in a much wider envelope than gen1. Even on gen1, once you're in CS mode, you'll have engine coupling (power split) above 36mph unless you are demanding tons of power (like passing on the highway). For highway cruising, you're experiencing power split the vast majority of the time.

Edit: JRRF beat me by two minutes :p
 

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It has been my experience with both Gen 1 and Gen 2 that only in very steep, hilly country does the engine rev near max RPM. OP's trip was, as he stated, in the plains, where ICE noise is very muted or inaudible. Also, after 29K mi. my '16 seems to run smoother than when new. (perhaps this is due to some dealer installed updates. I don't know.)
It is my understanding that the ICE lacks counterbalancers, relying instead on hydraulic engine mounts, which, for most driving except those steep hills, is perfectly adequate. The car is relatively expensive (still) and adding counterbalancers would just add to the weight and cost. Such an addition would make that little screamer Honda-smooth, but in a few years the ICE will be dropped completely.
 

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"in a few years the ICE will be dropped completely."

I can't wait until that happens! The Volt without the ICE is awesome enough......:)
 

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It has been my experience with both Gen 1 and Gen 2 that only in very steep, hilly country does the engine rev near max RPM. OP's trip was, as he stated, in the plains, where ICE noise is very muted or inaudible. Also, after 29K mi. my '16 seems to run smoother than when new. (perhaps this is due to some dealer installed updates. I don't know.)
It is my understanding that the ICE lacks counterbalancers, relying instead on hydraulic engine mounts, which, for most driving except those steep hills, is perfectly adequate. The car is relatively expensive (still) and adding counterbalancers would just add to the weight and cost. Such an addition would make that little screamer Honda-smooth, but in a few years the ICE will be dropped completely.
Typically a 4-cyl doesn't need a balance shaft until it gets larger than about 2.0 liters. (My old Porsche 944 has a balance shaft in its 2.5l engine.) A 90° V-6 can also benefit from one. (Have a couple of those too - Buick and MB...)

Great trip report! I've actually been to Broken Bow, Nebraska. A friend in college days was from there. Went to his wedding.
 
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