Just got back from an early Thanksgiving trip to Iowa from Denver, 640 miles one way. Heading out - almost due east - had a 20-25 mph wind out of the northwest, with this tailwind got an amazing 27.8 MPG. Coming home, 30 mph wind from the south/southwest (cross/one-quarter headwind), plus the gradual elevation gain from 1,000 to 6,000 feet, still managed a solid 23 miles per gallon with an average speed of 71 miles per hour.

The US fuel economy site shows this car should get 14 mpg city, 21 highway, so I was pleased with the results. Though I did not do the exact math at each fill-up, I believe the economy figures the on-board computer came up with were accurate.

 

I feel similarly impressed. On an average, I drive primarily highway - average 60+ mph and have onboard feedback that fuel consumption averages 24+ mpg.

Let's not worry about in-town... LOL Let's just say, I don't think the girl enjoys 'sitting' or waiting.

Always a good ride!

Sandy

 

Yes, these cats get good MPG.

On a recent 750 mile interstate trip we had my Vette along side my wife's XK8 for the trip. We saw 29.x USA MPG on the Jag dash fuel calculator. The 2 cars got almost exactly the same MPG with the Vette using 0.5 gallons more on the trip. Not too shabby for either car, especially for the 505 hp Vette.

 

Norm427.

What a fun trip to travel side by side in two beautiful cars!

Sandy

 

Let's have more of these driving threads.

Graham

 

When I purchased my 03, XK8 last year in Pompano beach Florida, I took two days to drive it back to New York State. While coming through North Carolina, with the cruise set at a very comfortable 79 MPH. I was averaging 28.1 MPG. I have achieved this , or about, on many long drives since. My cat averages over 24mpg on our about town jaunts. It's great! They maybe a bit finicky, but they have style,beauty, speed, power, and darned good fuel economy.

 

There is a very nice Apple application called "Road Trip" which I have been using since the end of August.

It enables you to keep track of many things without having to grind through the arithmetic every time you fill up. You just enter odometer, gallons, and price per gallon, and it does the rest.

You can also enter your expenses and service costs.

All in all, it is a very convenient and informative application.

For Android, I use one called "Mileage" which I don't like as well.

 

Did you ever check with actual gallons/liters going into the tank and distance travelled?

The lyometer is not always right and always optimistic

 

[QUOTE=Jochem00;869156]Did you ever check with actual gallons/liters going into the tank and distance travelled?
The lyometer is not always right and always optimistic[QUOTE]

I've done the math several times and it comes up basically the same as the on board computer.
Last August on a round trip between Lincoln, NE and Colorado Springs we go 29mpg with a low of 25. Again in September got it up to 30+ on a trip to Houston. I consistently get 26-27 on long trips. Around town though I can get 15+ I usually don't cause I can't seem to keep my heavy foot off the throttle. ;o}

I've really been surprised that I can get this mileage which is approaching what I get on our X-Type which is 30.

 

I have kept track of all my miles driven for a year and a half (30+K) and every gallon I've put in. The car's computer is almost exactly 1 mpg off. On average, it has shown 1 mpg more than what the math has determined.

Still, not too bad. Not too bad at all. A wonderful car.

 

A couple of things. First the onboard computer is the LEAST accurate in terms of mpg compared with several other cars I have owned. I am not sure why this is but with other cars my hand calculation compared with the car's calculation was always within 1 mpg while with the Jaguar it is often 3 or 4 mpg off.

Second--mpg has been nowhere as good as the numbers I am seeing here. While I am cruising on an open freeway at 65-75mph the instantaneous mpg readout is between 24 and 30. Unfortunately most of my driving is a few miles to and from work when I might manage to get 14 mpg. In cases where I do a mix of driving between fill-ups that include maybe one long decent freeway trip mixed in with my daily commuter drives the overall average might end up 18-18mpg.

Doug

 

Your apple roadtrip app is using the same data as your on board trrp computer is using.
Have a try to verify the computer vs your calcs