very happy with highway mpg

damn that's good

 

? Lol good? You could have gotten 60 +. Slow down lol

 

Just picked up a 2007 two weeks ago-traded out a PT Cruiser Rag Top. It got 22 mpg on a very good day, tail wind, down hill and at 60mph. So far I'm seeing around 45 mpg combined. Turns me happy every hill when I see 99.9 mpg...LOL

 

60 MPH. With A/C on. I do it every single day in my commute, with the up hill portion usually at 58-59 MPG and the downhill return at 61-65 MPG.

 

Agreed. Even on the highway, in addition to speed, it depends on your driving style, weather conditions, tire pressure, etc. Our most "accomplished" trip was averaging 50 mpg over 7500 miles, but that was with four persons, all the camping gear and roof rack, but we chose to only drive 60 mph.

PA P

 

And just to add some other comparison points, we recently went to Charlotte and back for a concert. We had three adults and one child, running with A/C set around 76 or so, and cruise set in the 68-73 MPH range for the entire trip (except the last 40 miles or so with my wife driving... she has a loath of machines in general, and will not use cruise). The entire trip of 450 odd miles or so was about 52 MPG. NC is a fairly flat state though, so your mileage will vary.

 

The way to Louisville is almost all downhill hwy and completely uphill the way back so I get about 59 mpg when you take the 89 mpg I get on the way there (I haven't tried the pulsing thing hwy because I just an learning) and the 30 or so I get on the way back. I set cruise at 50 and pray I don't get eaten by one of the 18 wheelers riding my nice person. (80 mile round trip)

When my husband drove we got 43 mpg because he drives 15 miles over speed limit... ALL the F_ING time!!!! I nearly cried... Throwing off my mpgs.

 

Must be small hills, because I can't get anything close to those numbers going up hills in my area, let alone level streets.

 

If you get 89 in one direction, and 30 on the return, the round trip average is 45, not 59.

 

The change in elevation is fairly small:


change: -7 ft total gain: 1198 ft grade: 0% max grade: 5%

However, keep in mind this is over 48 miles. 40 of those miles are on an interstate with cruise set at 61 MPH and A/C usually around 76-79F.

 

I know. I just did a oppsie in my mathy. LOL :doh:

The trip is 55.5 MPG. The trip home is actually 40 MPG which I didn't know because I have never reset before leaving Louisville until today. But it is around 30 MPG for the up hill climb.


If it maks anyone feel better I was Signal Intell with a language. So I didn't really do any of the math, just spent most of my time backing up the people who could pass thier spoken part of the Farsi test. Two years at DLI and I still can't speak it (right). But I can write and read novels.

 

Chicago to Syracuse, NY got 55mpg both ways at 62mph

 

Yeah 60+ MPG averages are the upper tail of the distribution, not the norm. Take a look for example at the results of this poll :

http://priuschat.com/forums/gen-ii-...oll-what-mpg-you-getting-in-your-gen-2-a.html

As you can see by far the largest number of users get in the high 40's to low 50's.

Personally I usually get tank averages of around 52 to 54 MPG, and while I can get 60 to 65 MPG on some low speed low traffic runs I usually get just a little under 50MPG at highway speed.

 

His math seems OK. in round numbers: 90 + 30 = 120 / 2 = 60

 

Hi Andy. It's interesting that simple averaging like that works ok for L/100k but it doesn't work for MPG.

Imagine for example an extreme case where you used zero fuel in one direction (pure electric and glide) and you used 8.4 L/100k (28 MPG) on the return trip.

In terms of L/100km you've used an average of (8.4 + 0)/2 = 4.2 L/100km. This corresponds to 56 MPG and is the correct figure.

Now try the averaging in terms of MPG. We got infinite MPG on the first leg and 28 MPG on the return trip so the average is ininity, meaning we used no fuel for the entire journey. Obviously that's wrong.

To correctly average MPG for a return trip you'd have to use the formula :

MPG_av = 2 MPG1 MPG2 / (MPG1 + MPG2)

So in the earlier example this would give.

MPG_av = 2 * 89 * 30 / 119 = 44.9 MPG

 

Most interesting, why must one use that formula?

 

You don't have to, you can just go back to the definition of average MPG: Total distance / total gallons. But for an out-and-back round trip, you will end up with the same answer produced by that formula.

For an example of why your formula doesn't work, here is a real-world situation with my non-hybrid and a ScanGauge (numbers approximated from memory). From Keystone CO climbing up to Loveland pass, about 9 miles: about 12 mpg. Return to Keystone while the engine is still warm: about 2000 mpg (basically, use engine to move out of parking space, then descend hill in compression braking with no more fuel. ScanGauge can display MPG up to 9999).

If the two separate numbers are simply averaged, the result of 1006 MPG implies that the round trip of 18 miles consumed barely over two ounces of fuel, even though the climb alone took 3/4ths of a gallon. This is an absurd result.

Uart's formula produces a round trip average of 23.86 mpg, implying a total of 0.7545 gallon over 18 miles -- i.e. 3/4ths of a gallon for the drive up, and under an ounce on the way down. This is a reasonable reflection of the actual outing.