BLE… I wasn’t talking about the same hill as your answer suggests. Please don’t take it out of context. How fast you would have to travel to maintain the same average would depend upon the time traveled within that ten mile total distance which if the same as 50, would be 90 miles per hour. Please read the "or " part of the statement which was conveniently disregarded in addition to the phrase “if at any time”.
Your example is not scientific but if it works for you, so be it. I can average nearly 30 mpg in my 4Runner too if I keep the speed below 55 with slight grades as I have done. But guess what, I could do better with no grades at all. Bottom line; it’s still a low 20s mpg highway at 65 to 80 mph and traveling around at less then 55 on slight grades does not prove a thing when wind resistance at higher speeds, which in part, determine our EPA figures, are disregarded. EPA uses level ground.
It is my contention that a car(yours) does better than highway or average mpg due to lower non stop and go speeds, and not because of slight grades. Just google terrain and it’s effects on mileage. I don’t feel I’m alone.
“As CR points out in their tests, when traveling, even with regenerative braking, the Volt with the engine running averages only 29 mpg both city and highway, much less then a Corolla.”
I suspect that when the Volt runs in engine mode, it’s because the battery has been used up and the engine is working to recharge the battery in addition to powering the car. This may account for the dismal fuel economy in engine mode.
Even though the Volt is officially a series hybrid, for efficiency it does help spin the wheels, I believe through the drive to the wheels but at a much lower % (10 to 15) then a true parallel. Without a charged battery from an outlet, as long as the battery is depleted and the car is driven the only way the car can move past the initial 35 miles give or take, is by the gas motor running with the mileage continuing to be as tested by CR. It never improves until it is charged from an outside source.
I don’t believe the gas motor will ever bring the battery up to charge enough to run it on electricity alone while driving as it’s chage capability is only allowing the electric motor to contribute the other 90%. Hence, past it’s depletion state for extended driving, it continues to be worse then a Corolla to perpetuity. If you have read anything different, I would be interested in hearing it. So not being a true series or parallel hybrid, you could call it a hybrid-hybrid. ;=) I guess. And, at $35 k I feel it’s a public relations rip off.
In it’s defense, I feel with out a traditional transmission and driven mostly by an electric motor, it has the potential to save the driver $$$$$ in other ways; mostly by very low maintenance and repair. Unless GM has built in some maintenance requirements to make themselves money, it could become one of the most reliable vehicles they have ever made, therefore necessitating the high initial cost.
Interesting discussion. Don’t say that what the OP states is impossible, even though at first glance it seem so.
While engine efficiency has been mentioned, one thing hasn’t. That is something we call “Pumping Losses.” When an engine is running, it takes force to turn the engine over against the semi-closed throttle plates. This is the force that creates what we call engine vacuum.
When going uphill with a very high throttle opening, the engine has less “pumping losses” and due to that and other factors is operating at higher efficiency. When going downhill, the throttle is more closed while we fight gravity to not go too fast, and this is “engine braking.” During this phase, the computer shuts off the injectors. Going downhill, the pumping losses are being used so we need less wheel braking, and do not hurt us.
Thus odd as it seems, modern cars in some cases just might get better mileage in hilly terrain. Strange but true?
I’ve been recording the MPG since I bought a new 2018 Nissan Versa (manual transmission), now with 65000 miles. I live in the Cascade mountains of Oregon at 4000’ elevation so 75% of my driving is on 2 lane mountain roads and some is more or less flat 2 lane roads out across the desert. The Versa does indeed get slightly better MPG in the mountains, about 43 MPG vs. 40 MPG.
Interesting topic…
Only 2 members are still active from the 14 year old discussion… lol
I would say driving up hills doesn’t require much more throttle nor fuel than cursing along the flatish roads, and since no throttle to come back down the hills, it probably does use less fuel…
Someone should have someone monitor the throttle input % from live data over x miles going up a hill vs a flat road, to see the difference… Or watch (video) the MID (Multi-Information Display) on the dash to see the difference, but still rather watch live data though… I guess gear changing/selection at the right times will affect the outcome also…
I’d almost bet ya it is not much difference in throttle %…
Welcome @piloto555_193153 As Dave mentioned this is a 14 year old thread. You can see that from the upper right corner of the panel of the last comment.
I think your analysis is spot-on. I have seen the same.
I played around with this concept on a long trip in my 1984 Corvette. It also seems as if a small additional benefit can be gained by slightly speeding up on the flat approaching the hill. As you climb, hold the throttle steady and letting ths speed drop a little then lifting as you roll down the other side.
This is where being able to use a few different emoji to choose from would be good (instead of posting), like a sad one instead of only a thumbs up one, that just doesn’t feel right even if you knew it was for the info and not the loss of forum members…
