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Volt MPG at 80-85 MPH?

9K views 26 replies 22 participants last post by  rkjnsn 
#1 ·
Speed limits are going up in MI. Anybody have a hold mode mileage number 80-85 MPH?
 
#3 · (Edited)
I imagine my Gen 1 gets around 32 mpg at 75 mph, but it really depends on wind and other factors at that speed. My guess is around 30 mpg?

Typically, increase in speed limit means fewer people will be driving substantially slower, not that the faster traffic will be moving much faster. For example, with a 75 mph limit I wouldn't expect traffic to be moving much faster than 80 mph. The reason people drive 10 or 20 mph over at 55 mph is probably that the speed limit wasn't realistic in the first place. When you start getting up to 75 mph, the speed limit is probably more reasonable so I think people are less inclined to drive 10 over still.

When speed limits went from 65 to 75 in Wyoming, I don't suppose traffic speed changed that much. Now they are at 80 mph in many portions, and most probably drive 75-80 mph still. They didn't drive much slower than that when the limits were at 65 mph. Now I live in Iowa, and they went 65 to 70 mph but I didn't notice a change other than with the slower traffic which was just obeying the limit.

Source: https://www.ibiblio.org/rdu/sl-irrel.html
 
#6 ·
Honestly, the difference is unlikely to be much at those speeds. The aerodynamics of the car determines how much power you need, and to get a certain amount of power you need to burn a certain amount of fuel. Efficiency of the engine will of course make a difference, but probably not a lot. What did you get in your gen 1 at those speeds? Maybe add 10% for gen 2.
 
#9 ·
I'm going to go with 37-ish too. You get up around 80mph on interstate 8 in AZ. Hard to tell exactly because I didn't reset the trip meter for that leg of the trip. I got around 40 mpg total the last time I did the trip, but the weather was bad so I was going slower.
 
#10 ·
80mph is getting pretty fast for a lot of drivers, especially when they sit less than 10 feet behind you at that speed. Here on Ontario, Canada, the speed limit is still 100kph which is about 62mph. Most do closer to 75mph though. The slower traffic is the problem but they refuse to raise the speed limit. It is less safe with such a speed difference.
 
#11 ·
That is the MINIMUM speed in California....just to survive and not get run over :)
Averaging all electric still on my 2017 and 44 mile round trip.
the computer says about 89....but without using gas :))
 
#15 ·
Pretty much the same on the turnpike in FLA and sections of I-75 and I-95. Left to my own devices, I would drive 78 in a 70 MPH zone, but I frequently get up in to the lower/mid-80s for long stretches due to traffic conditions.

I would also point out that running in a pack of cars, while stressful, yields a significant MPG benefit (drafting). For safety and courtesy reasons, I would not voluntarily draft off of someone, but sometimes the flow of traffic dictates.
 
#12 ·
The area in Canada I drive the most often are 120 kph or close enough to call it 75 mph. The 80 kph (50 mph) two lanes for hundreds of miles do get old though. FWIW, 65 mph is the fastest speed limit I've seen in AK, but most do 70-75mph. I bet if they fixed the roads and raised the speed limit, we would all do the same. Of course in the winter, I'm usually going much slower.

I never got great hold mode mileage in our 2013 Volt. So eve if I had a Gen 2 to compare you wouldn't like my answer.

They gave up on speed limits on I-275 in GA. They removed the signs, not that they are saying "no limit".
 
#13 ·
My ELR gets 30 to 32 mpg at 80+. Of course that's an inefficient (relatively) Gen1.
 
#16 ·
I see no issues with driving 80 mph on nice long stretches of the interstate..however, my issue is that most people don't even come to close to maintaining a safe distance. If police officers would enforce the 3 second rule of space between cars, driving at higher speeds would be MUCH safer. Has anyone ever seen a multiple car pile up? Ever wonder how so many cars could be involved in one crash? They simply didn't have a safe distance between them.
 
#19 ·
Is that a real rule or a rule of thumb? Presumably in your State. With the "following behind" sensor in the Volt, I feel comfortable following other cars at 1.0 to 1.2 secs. But at those distances, you get cars switching into your lane. I think pack driving must have gaps of 0.6 secs or so.
 
#17 ·
My pure gas MPG after a 300 mile trip going 75 the entire time on the highway (1 quick gas stop towards the end of the trip, otherwise 75 mph all the way) was 32.5 mpg. Temperatures were right around 30 the whole time, dry conditions. I started the trip counter right after it switched to the ICE. 9.3 gallons burned going 305 miles.

I have the shorter air dam, wind buffeting kit, and Bridgestone Driveguard runflats on my Volt, so the MPG likely took at least a 10% hit compared to completely "stock" 2012.
 
#18 ·
Michigan is like Wisconsin, they want more gas tax.

Michigan figures this change will increase road tax revenue 20%, so guess what?

Our state did something similar at the beginning of last year and highway deaths went up 35%
 
#20 · (Edited)
For a tired and bored driver, reaction times are pushing a second in duration. Driving in standard, high-speed, bumper-to-bumper traffic is definitely not safe, no matter how safe you feel. One mistake or malfunction can causes multiple-car pileups that dominoes back until a sufficient following distance gap is reached. I just keep my 2-3 second gap and let people pass and cut in. It doesn't bother me all that much and it's safer.
 
#21 · (Edited)
I drove my Volt from Boston to southwest Florida a couple summers ago, covering 1500 miles in about 24 hours. We were driving between 80 and 85 pretty much the whole way and went through the mountains of Pennsylvania and Virginia on I-81 instead of the flatter I-95 (to avoid northeast traffic, we were in a hurry). 36-38 MPG I think. I've discussed it somewhere in the forums here but I can't find it now.

edited to add - sorry, I completely missed that this is a question for Gen2 Volts.
 
#22 ·
You can safely drive beneath a speed limit. A speed limit is the fastest that you can legally travel, not the fastest that you can safely travel. I typically travel on the freeway between 55 MPH and 65 MPH. During snow and ice conditions, I often lower that to 35 MPH to 55 MPH, depending on visibility and warmth of the ice. High-speed traffic, not slow-speed traffic, is the greatest hazard on winding mountain roads, including the freeway. The shaded area of freeway in Officers Gulch is a particularly dangerous section of road, as well as Vail Pass and the Continental Divide. I have witnessed hundreds of accidents during the past decade. My lifetime average with a Generation I Volt is 83 MPG, with an average of 42 MPG entirely on gas generator.
 
#24 ·
I thought 2-second rule was the standard, which doubles in rainy conditions.
 
#25 ·
My last long trip was from Toronto to Florida, 1500 miles in CS mode, Avg sped about 75 or so and I got just under 40 mpg. Car was fully loaded so I was quite heavy.

Since the last software update I have annectdotely noticed the mpg going up a couple of mpg from what it used to do. Won't really know for sure until I drive home in the spring.
 
#26 ·
When I learned to drive in the early 1970s, the recommended following distance was one second for every ten miles per hour (60 mph = 6 seconds, etc.). Of course, one must remember what the capabilities of cars were back then, and also (people don't tend to realize this one) that there were only 1/3 the number of cars on the road back then, compared to what we have now...
 
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