Learned a lot about my car in its 2900 mile round trip to South Dakota so thought I'd share it.

One thing I wondered that I never could find any info on is atual ful economy a high speeds. Across South Dakota I tested this and on flat land it stuck at 25mpg at 100 mph cruising and a decent 30mpg at 90mph. The best speed where it drops contrary to what I have heard is 85 where it can consistently stays at 38 mpg, 41 at 80, 44 at 75 and 47 at 70.

Anywho other thing I learned is what happens when you run out of fuel. It kind of disapointed me first off cause my add fuel warning came on 10 miles before I ran out so now I started taking my avg mpg and times by 11 and works out nice. But as for as smart this car is why not give it a hey I am out of gas warning instead i simply got a there is a problem and the big red Exclimation point, but anywa I know now.

I moved from a 230 hp WRX to this 110 hp car and not disapointed with its ability to still let you play. Altho as everyone seems to say it needs some new tires but will wait to wear these down.

One last thing it was very comfortable I drove 10hrs the first night, 20hrs the next day and another 18 the next day and was never really all that uncomfortable, it does have the leather seats never liked them much but they seem comfy. Only comaplint is the steering wheel seems way to far away to get a comfortable crusing grip on it seems to force you to use it in the way they tell you too maybe there is a reason for that but makes my hands tired after hours of driving.

9300 miles in 6 weeks and loving it.

 

BTW, this is excellent data points if we can get these additional data points:

MPH MPG
100 25
90 30
85 38
80 41
75 44 (measured 39 MPG, 03 Prius)
70 47 (measured 49 MPG, 03 Prius)

Duration of each segment?
Temperature? (Especially segements above 70F)
Wind conditions?
Tank or MFD measured?
Includes accelleration to speed and decelleration?
Tire pressure?
Oil level?
AC? "AC at 72" - it was on auto?
Estimated weight of driver, passenger and stuff?
Interstate and route?
I see the combined segments in the database.

Thanks,
Bob Wilson

 

Neat stuff! 25mpg at 100 mph is very, very good. Did your fillup mpg actually agree with what your digital display told you? Obviously, you couldn't run an entire tank at 85mph, but in general did your display mpg match your actual calculated mpg?
I ask because my display is always about 2-3 mpg optimistic, and my general impression is that the digital displays are usually optimistic-across all brands/makes.
I did a recent trip, and my digital numbers were roughly what yours were-68mph 49 mpg.
Thanks.Charlie

 

Hi,

I've added your MPG to the MPG vs. MPH chart:


If you don't see the NHW20, high-speed chart, reload the page to update your browser cache.

Bob Wilson

 

looks nifty in a graph really shows what I found anything over 85 is terrible for fuel economy.

BTW was easily 90°+ whole trip
5-10 mph wind
had two 100 pound girls and my 160 pound self not much for cargo maybe 80 pounds
Trips were 5-6hrs most it would run on a tank
tire pressure of 37 front 35 back
Oil was just changed before trip
All I-90 west travel straight and flat as can be
AC auto at 72 was blaring whole time tho as it was sunny and from 90 - 117°F the fastest segments of 90 to 95 were at the highest temps of 117°F
All included accel / decel seped was kept exact for hundreds of miles south dakota is nice for that.

I stil lfind it odd you see no decrease in power even crusing at 95 mph when the battery is purple with one bar for long periods


Going on another cross country trip in mid august threw North Dakota, Montana, yoming, utah and many other states will make sure to keep even better track on next trip and can compair from this one. Tring to do more non interstate on next trip tho as highways are so boring.

Some of my gas receipts turned black it was so hot in the glove box I did it all on the mfd as I find it near spot on.

 

Thanks,

I'll update the chart:
Two things:
1) consider getting tire pressure caps and runing 42/40
2) I suspect that notch is flow-separation, which I strongly suspect is happening with my NHW11 just above 65 MPH
3) check oil level, about 3/4 of full is optimum

At higher speeds, there is a current flow from MG2 to MG1 and the battery is 'along for the ride.' MG1 needs the current to balance the ICE torque so it pulls it from MG2 working as a generator. This is one reason why non-hybrid folks just don't get it. Guess what, the MG1 power is used to move the vehicle forward so it isn't lost . . . <grins>

If you can on future trips, see if you can record start-and-stop locations with enough detail we can find the altitude. Ken has shown how to figure out the tank-to-wheels efficiency if we know the starting and stopping altitudes and the speeds on at least three, preferably four legs is kept at the same, constant speed. With three legs, we can calculate the efficiency and with four, we can identify and drop any problem leg. It is just a series of simultanious equations.

GOOD LUCK!

Bob Wilson