Here's the updated MPG & OP Costs (*) for my 2007 Coupe:





(*) - Does not include depreciation & insurance

I participated in 2 road events during 2023:
a) Crossfire Fall Rally in SEP: total miles = 599.5; total gallons = 22.12; Avg MPG = 27.1
b) Smoky Mountain Drives in NOV: total miles = 700.0; total gallons = 27.58; Avg MPG = 25.4

 

Excellent charts! It's interesting to see how close the MPG has stayed over the years.
By the way, do you do taxes?

 

Interesting discussion about Crossfires and gas mileage. I get typically 29 on highway trips @ 70 mph and about 24 to 25 around town. What's even more interesting to me, however, are the comments on this thread that seem to be resentful of the very discussion of mpg, as if it violates an unwritten rule for "sporty" car owners.
However, for me, just like spending too much for a car takes some of the fun out of its ownership, so does unnecessarily getting too low of gas mileage. To me, driving fun and as-good-as-possible gas mileage go together like root beer and vanilla ice cream. Two positives that together equal a third.

 

I get 24 to 25 on highway, as long as i stay under 100,, most of the time around town i get maybe 9 to 10,, you see my shoe has a magnet so it is hard to remove from the floor.

 

I think those posters who pooh pooh the mileage question are a little shortsighted. Knowing the average MPG for your car can be useful as a diagnostic - there are many things other than being a lead foot that can affect your gas mileage such as a faulty camshaft sensor, bad plugs, bad gas, map going bad, o2 sensors, clogged air filters, etc... Say most manual NA xf get around the high 20s mpg, and you get in the low 20s or teens, then maybe that's a sign of a camshaft sensor going bad. At least the mpg might give you a hint to look for a potential problem before it becomes a major problem.
My car is a hanger queen, manual, NA, 91 octane gas, and only gets between 20-25 mpg on the short drives I go on during the weekends. (I think some of the low mileage is due to evaporation of the gas while its sitting waiting for the next drive.)

 

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I like the "Smiles To The Miles" factor myself. When my scan of the IP can see 1/2 or less in the fuel gauge, I tend to slip into my fav fill-up station. Too many things to mention can cause a bad miles to gallons ratio so if a tank or two doesn't bring it up to where my particular driving habit/gauged approximate historical location, I'll look for a reason. BUT, only after I rule out bad gas (from the 3.2L powerplant).


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Sports cars are not known for fuel efficiency. They do, however, offer a thrilling ride and exciting acceleration. Take your pick !

Q: Why do sports cars have low MPG?
A: Because of the placement of the right foot.

 

2007 Limited Roadster, NA, I get 26-28 with mixed local and highway driving, but generally under 70 mph. On the drive from Tempe, Arizona where we bought it to our home in southwest New Mexico, I got 30 and that was with hard-as-rocks ancient tires and average speed of 70-80. Almost always use 91-93 octane gas ... added a half tank of regular on a road trip because Premium was really overpriced. Car ran fine. Completed a preventative transmission service last month, feels smoother and a little quicker off the line, but a lot of that is me becoming comfortable with the capabilities of the car as my capabilities increase.
Yes, mileage is a good diagnostic, especially if there is a sudden drop in mpg. It's an early heads-up.
And I do not drive with an eye on the gas guage. Driving this car is too much fun to worry about mileage ...

 

Great comments! A reminder to many, the ECU has a fuel table that modifies performance within sensor/hardware that by design limits damage/performance (fuel/air vs designed/installed sensors), THIS is why filling with 91 octane is not as bad as some who poo-poo this, as they believe the more they spend the more righteous they sound about the subject. Thank you for mentioning this! Happy Perma-Grin folks! Flame away (those who choose to), I can take it, BUT it'll fall on deaf ears...


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99% of preformance cars only need 93 oct when the peddle is on the floor, Very few car manufactures will tell you to use 87 oct or, 93oct for more power,, but ford does on a 2016 fusion turbo it says 87 oct is 210 hp or with 93 oct gas 235hp ,, i am going by memory so don't quote me on the hp but i know i am close jim
I remember seeing a Modern Marvels on gasoline and they repeated that several times ,,, and all 93 oct gasoline is the same, so is all the 87 oct,, the additive is added just the gas in put into the tanker trucks ,there are usually 3 different sections on each truck,one for 93 one for 89 and one for 87 . jim

 

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I run a V-Tech tune on my SRT6. He sent me a file for 91 and one for 93 octane. I have now switched back and forth a few times as I wasn't a believer there would be a difference but there really is. I don't have Dyno numbers to prove it but the 93 seems to tickle out more HP than the 91 tune does.

Is there an app you guys use to measure MPG or do you use good old math? What's the best way to measure MPG?

 

I just use simple math. You can see in my Post #61 of this thread, I keep pretty good records on both MPG & Operating Costs (less insurance & depreciation). It really is just a matter of recording the miles driven on the Trip ODO whenever I fill up, resetting the Trip ODO to start a new cycle, recording the overall mileage on the Main OPO, & grabbing a receipt from the pump. That way I know Gas Price & Total Gallons to fill up. I record this in a Steno Notebook (6" x 9") that I have for each vehicle. Then I've got a MS-Excel file I use to keep track of both OP COSTS & MPG on an annual basis, plus any expenses I consider worth recording (the Steno Notebook has all expenses for the respective vehicle). I have this file for each of my vehicles. The file for my Crossfire is attached.

 

Does anyone know what the V8 swapped crossfire get?

 

Great way of doing it and figured that's what most do but was wondering if any apps like Torque are in any way "real-time" and accurate. Thanks for the post!