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Mileage question

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Old 11-10-2007, 12:51 AM
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Default Mileage question

It has been a long long time since I had a math class.
I took a 3 hour road trip this evening, filled with fuel before I left, zeroed the trip meter, and refilled when I got back.

miles traveled: 235
fuel used: 6.533 gallons
The way I figured it, I got 35.97 miles per gallon. Can this be right? I have never observed better than 25 mpg in this Bonneville before.


All the conditions were great, temperature in the upper 60s F, tires properly inflated, windows rolled up, no AC, just me and another lightweight person, a minimum of crap in the trunk, and I used cruise control almost the whole way. About 30 or 40 miles were in town, so I'm calling this a solid 36 miles per gallon on the highway.
Oh, and if anyone is interested, low grade gas (87 octane) is $3.099 here.
Old 11-10-2007, 03:04 AM
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I've gotten 32MPG in my bonne.

Food for thought

Ed
Old 11-10-2007, 09:33 AM
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The last trip to CA I averaged 32mpg at 70-75mph.

No, it'* not unheard of.
Old 11-10-2007, 11:11 AM
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I find if the gas pump clicks and stops a little prematurely it can skew the numbers quite a bit. It'* how I got 46mpg in the Civic on one road trip only to get 28mpg the very next tank... I usually get ~35mpg mixed driving and the 46/28 tanks averaged to be about the same.

Less gas went in and the tank wasn't full
Old 11-10-2007, 11:42 AM
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On trips, I often get 30+ mpgs. It'* all highway and how you drive. For example I get 29-31 MPG when I drive but when my 'rents take their turns in driving, they get 35 MPG out of her. And that'* with 3.05 gears.
Old 11-10-2007, 11:46 AM
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Originally Posted by jr's3800
I could never get 35... 30-33 Sure... But My foot won't allow much more than 32
God bless them and their way of thinking "Less is more"

But for me, if it'* 30 MPG, I'm good!
Old 11-10-2007, 01:50 PM
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I just wasn't sure I did the math right. I have recently found a leaky vacuum line near the firewall that I believe has been ruining my mileage for a while. I didn't realize how much it affected mileage until I ran the numbers.
I have 2.97 final drive ratio, lightweight LE trim package, split bench seat, and I had the cruise set on 75. Also the terrain was eastern Oklahoma, so it was pretty much flat.
Whenever I am planning to check my mileage, I use the exact same fuel pump before and after to eliminate the variance in full stop levels.


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