Speed vs. MPG charts (post 'em if you got 'em)

[bluejoey]

Originally Posted by rbrowning

I wonder what caused the hump in the curve for the Corolla? Aero? Surely it would have been in top gear before 60.

That top gear is at 43mph, I believe.

Found some more...

Assorted cars, including Yaris and Insight II by Consumer Reports, courtesy of MetroMPG (as with the Auto Bild chart)

[jamesqf]

I wish it was as simple as speed vs mpg for me. In the Insight, mpg is very noticably affected by things like temperature, winds (even light winds), road surface, & driver mood - yes, I do get better mpg when I'm happy about where I'm going. I haven't figured out the exact phase-of-the-moon vs mpg chart yet, but I'm sure it's there.

[PaleMelanesian]

Here's another. My Odyssey, with the same drivetrain, predictably matches these results.

It also shows the bump when it shifts into top gear, like the Corolla above.

from http://ecomodder.com/forum/showthrea...nomy-7552.html

[SuzukiSteve]

Originally Posted by Frank Lee

About 1233 rpm @ 55 mph- jealous!

You would only get 1233rpm at 55mph if you forget to shift into 6th. Im jealous of the 1500rpm at 110mph! Those are some TALL gears.

36.5 mpg is very impressive for a 7.0 liter. Wow.

[EdKiefer]

Some of those graphs show best mpg at very low speeds like the 2006 Toyota Corolla 1.6L Auto and vette . you think its in high gear at such low speeds or is it somehow getting better mpg not in high gear .

[euromodder]

Originally Posted by rbrowning

I wonder what caused the hump in the curve for the Corolla? Aero? Surely it would have been in top gear before 60.

Originally Posted by EdKiefer

you think its in high gear at such low speeds or is it somehow getting better mpg not in high gear .

I'm not surprised by it (only slightly so by the speed where it happens).

I have a hard time getting decent FE @ 90kph/56mph in 5th (top) gear, and it's the same with anything below 60kph/37mph in 4th.
The (smallish) engine revs low at these speed/gear combinations, barely 1600rpm.
I suspect it simply doesn't have the power to cope with the high loading.
A little bit faster, and it goes straight into its FE sweet spot around 100-105kph/62-65mph

Coming out of a deceleration phase and ending up in these situations, mpg will be OK. But any incline, or any attempt to accelerate will instantly result in a massive drop in mpg.
I've recently started to go back to 4th rather than stay in 5th, to come out of a tunnel on my commute and it seems mpg on the climb is better (or not as bad) in 4th.

I think I'm going to go ahead with an ECU remapping that gives more power and torque at lower revs.
I could use the odd extra 50 Nm around 1400-1600 rpm to bring the rpm down by 200-300 rpm - and drive in a higher gear.
As it is, the car needs a fair bit of throttle to get going smoothly.

HP and torque diagram of the Rica E-power remapping :

[EdKiefer]

Originally Posted by euromodder

I'm not surprised by it (only slightly so by the speed where it happens).

I have a hard time getting decent FE @ 90kph/56mph in 5th (top) gear, and it's the same with anything below 60kph/37mph in 4th.
The (smallish) engine revs low at these speed/gear combinations, barely 1600rpm.
I suspect it simply doesn't have the power to cope with the high loading.
A little bit faster, and it goes straight into its FE sweet spot around 100-105kph/62-65mph

Coming out of a deceleration phase and ending up in these situations, mpg will be OK. But any incline, or any attempt to accelerate will instantly result in a massive drop in mpg.
I've recently started to go back to 4th rather than stay in 5th, to come out of a tunnel on my commute and it seems mpg on the climb is better (or not as bad) in 4th.

I think I'm going to go ahead with an ECU remapping that gives more power and torque at lower revs.
I could use the odd extra 50 Nm around 1400-1600 rpm to bring the rpm down by 200-300 rpm - and drive in a higher gear.
As it is, the car needs a fair bit of throttle to get going smoothly.

HP and torque diagram of the Rica E-power remapping :

right, I would assume somewhere around 40-50 mph would get best mpg as this would be approx speed of high gear . But in that first graph of 2006 Toyota Corolla 1.6L Auto it gets best at 24 mph, no way it is in high and as noted above the next bump is probably the high gear one .

I am just surprised it can get such good mpg, even besting high gear speeds .
If the engine is to small for gearing and weight, I would assume best would just move up on rpm scale, not go down in speed .Yes I realize most small engines peak there TQ at like 4-5k rpm which doesn't help real low rpm cruising .

[bluejoey]

Originally Posted by EdKiefer

right, I would assume somewhere around 40-50 mph would get best mpg as this would be approx speed of high gear . But in that first graph of 2006 Toyota Corolla 1.6L Auto it gets best at 24 mph, no way it is in high and as noted above the next bump is probably the high gear one .

I am just surprised it can get such good mpg, even besting high gear speeds

http://ecomodder.com/forum/showthrea...ic-6710-2.html

MetroMPG talks about that here too. It would be interesting to find out just how many cars out there can achieve their best mpg just below top gear.

[EdKiefer]

Originally Posted by bluejoey

http://ecomodder.com/forum/showthrea...ic-6710-2.html

MetroMPG talks about that here too. It would be interesting to find out just how many cars out there can achieve their best mpg just below top gear.

That answer a lot of questions , thanks .

[MetroMPG]

Good thread!

Originally Posted by RobertSmalls

We should all include the source of our data, so folks know how good the data is.

Yes, please! Links are also nice. I've added links to some of the posts above.

Also, when Wayne Gerdes reviews a car, he does an mpg vs mph test on it.

That's excellent. Ideally, that kind of info would come with all car reviews. Or at least with reviews about so-called economy cars.

Originally Posted by Frank Lee

Periodically we get claims of higher fe at higher speeds, or at a certain speed range that isn't near the low end. I suppose it's possible if an engine has a peaky BSFC combined with certain gearing and loading... but most of the time I'm tempted to chalk those claims up to faulty fe calculating.

That's exactly why I wanted to do that Corvette Z06 test: to get some actual data to point to when that tired old line comes up.