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

[gone-ot]

Originally Posted by fcporto

Due to recent activity in this thread, I am re-posting my previous graph with some changes, namely:

1- new graph type, that takes into account the amount of Km made in each test run (and a rather colorful one...)
2- new data from recent runs
3- values are corrected for the computer average error (6.1%)

Mercedes C200 CDI (diesel), estate, manual gearbox

Did you try seeing if your numbers possibly yielded a higher correlation coefficient (R^2) using the "constant product" relationship formula, ie:

K = MPG × MPH ...and, thus, MPG = K / MPH

[Blue Angel]

Originally Posted by PaleMelanesian

What rpm do you run at 60 mph? I'm at 2800.

Originally Posted by Blue Angel

...If I remember right, it's reving almost right at 1500 @ 50 MPH, so at 60 it would rev about 1800 or so. It's a .61 6th gear with a 3.83 final drive and a 26.3" tall tire (215/55-17).

I worked it out mathmatically. Using 795 revs/mile for that tire (Source=TireRack), at 60 MPH the engine is turning 1857 RPM. It may turn just a tad slower in reality as I have my tire pressures set high, about 49 psi cold on the fronts (may or may not make a difference in revs/mile).

Nice tall highway gearing, for sure, but I find I spend most of my time in 6th even around town. Part of my commute goes through a windy slow stretch along the Ottawa river that has a few gentle grades here and there. Traffic depending, as long as I'm able to keep my speed above 33 MPH (~53 km/h, ~1000 RPM) or so, this little 1.4T lugs the car up through that section with little complaint.

Drop the engine below 1000 RPM or so and torque drops off significantly. I get the feeling cam phasing angles change below 1k RPM to prioritize smooth idling over torque output. I don't think the turbo is contributing at all at those low engine speeds.

For such a heavy car with a small powerplant I can't complain.

[101Volts]

FYI, The site I linked on Page 11 has details for cars that are even fifty years old. It doesn't have every car ever manufactured listed, But there's a lot of info there. Whether or not it's all quite accurate, Who knows. But it did help steer me away from purchasing a 1991-1996 Roadmaster Wagon.

[NachtRitter]

For the VW Mk4 TDIs:



From MPG at MPH chart - TDIClub Forums

[Saskwatchian]

Since my last graph I have gone a few more km, upped the tire pressure from 32 to 40, replaced the two rear tires to match the fronts, replaced the doughnut with a full sized spare + added bunch of other gear (probably net change +60 lbs)





Blue is before (99 points, 1543 km total)
Red is after (81 points, 1884 km total)

In a way it is too bad I did so many changes at one time so it's hard to say what had what affect but the car handles a bit better now and I have much better piece of mind driving in remote areas while any change in milage appears to be a wash.

Oh and I did some more controlled tests on AC on -vs- AC off and it appears to affect my consumption by about 0.2 L/100km @ 100km/h. At $1.40/L I will gladly pay the 14¢/hour it takes to keep me cool and comfortable with the AC on in the summer.


EDIT: does anyone know why my my graph is so small?

2nd EDIT: Thanks Metro

[MetroMPG]

Fixed the graph

[Vekke]

Measured fuel consumption data from Finnish car magazine called Tekniikan Maailma aka TM.

There are measured fuel consumption data at speeds from 60,80,100 and 120 km/h.

Work is not mine, but should be accurate. They usually use flow meters in fuel lines in their tests. Test are done year around so some test are at winter conditions. they have regular test route which they use. Speed limits are higher on summer so they claim it will even out the difference of cold weather.

https://spreadsheets.google.com/spre...4WnZjSUE&gid=3

Might require google account to use.

If you press the buttons it will sort the list from best to worse.

Melu = Noise
Kulutus = fuel consumption
kulutus kaupunki = city fuel consumption
kiihtyvyys=acceleration
Rengaskoko=tire size
rengasmerkki=tyre mark
välitykset= gear ratios

For rest details you can use google translate .

[MetroMPG]

Originally Posted by MetroMPG

From: Speed vs. mileage/fuel economy chart - Mirage 1.2L 5-spd

Some data confirming the earlier chart for this car: a new U.S. owner is reporting 49.5 MPG (fill-up calculation) for a brand new 5-speed Mirage over a 400 mile trip with an almost 60 mph average speed, including a 10-20 mph crosswind on the return leg.

That was with tires set at 32 PSI and no other mods. A/C was off, presumably.

Test drove a 2014 DE manual transmission today - ordered one (U.S.) - Page 2

[basjoos]

I finally got out and did a series of steady state speed vs. mpg runs in the Aerocivic. Finding a sufficiently level road was a search (this region is called the Piedmont for good reason), but I found a 6 mile stretch of highway that paralleled a railroad right of way that was very level and had only a 53 foot height variation along the 6 mile stretch. Elevation of test road was 700 feet above sea level
Air temperature at time of test 91 degrees F.
2 runs in each direction at each speed. Remained in lean burn at all speeds tested.

I don't have a graph generating program on my computer so I'll just list the numbers. If anybody wants to plug them into a graph, go ahead.

50 mph 95mpg
55mph 87mpg
65mph 77mpg
70mph 71mpg

[Daox]

That is incredibly impressive. Thanks for posting that info Basjoos.