Fuelly

[Darlo]

You still will never beat me! Mwah HA HA HA HA

[Pu241]

Never is a very long time!

And I suspect some preventative maintenance on my engine/car could help considerably.

Also had I not included my 39.4 mpg tank when I first picked up the car, my average MPG would be closer to yours. Of course that will be less important as more tanks are added. Much as your 51 MPG tank is reduced in your average of 17 tanks.

You do bring up and interesting point, how do we know if we've won?

[Darlo]

We should set a time limit......Say Christmas? And the losers must send the winner $5 each? or something like that....That would be fun....

[stash2000_2000]

guess I have to use the 155/80-12's 1.03% cause thats what I'm running

[Darlo]

guess I have to use the 155/80-12's 1.03% cause thats what I'm running

It is not 1.03%, it is 1.03......This means that because your tires are a larger diameter, your odo is saying you are going less than you actually are, thus you multiply by the ratio that you are out by......

For example, if the diameter of your tires is 5% larger than stock, you must times the miles your odo says you travelled by 1.05 to get the "actual" miles travelled for that trip.

The best thing to do is to actually test your odo by way of GPS or mile marker to see if it is out at all....

[Pu241]

John your 155/80-12's are 3.0% taller than stock 145/80's. Thats whats causing your speedo to be off a little. When I fill up the 92 I multiply the miles by 1.03 to correct it.

After reading this again, I need to correct something.

My Odo is reading about 2.5% higher than my GPS.
Example:
GPS = 100
Odo = 102.5

I could legitimately use my Odo for MPG calculations!

[MTec007]

Without the option of using a "trip Odo" someone might think I was "cheating" if they never saw consecutive Odo reading due to the correction factor.

you do know that fuelly does have that option, right?

just edit your car,

example:

Edit a Car: The Bomb

Current Type: 1988 Ford Festiva [change type]


Track fuel-ups with trip miles/km or odometer reading? [more info]

() Odometer () Trip Miles (or km)

[Pu241]

you do know that fuelly does have that option, right?

just edit your car,

example:

Edit a Car: The Bomb

Current Type: 1988 Ford Festiva [change type]


Track fuel-ups with trip miles/km or odometer reading? [more info]

() Odometer () Trip Miles (or km)

Uh, that was my point!
If it wasn't for having the trip Odo option I wouldn't use fuelly, because my odo readings would have to be corrected each new tank and the odo readings wouldn't be sequential.

[Pu241]

Another tank burned and entered into fuelly.

[Darlo]

Another tank burned and entered into fuelly.

Well done! After looking at your history, I would say you should remove the data point where you were towing, as this is basically comparing apples to oranges. I am not saying that we remove data points that are not as good as we hope them to be, I am saying if you are towing, it is not a good indication of the "normal" fuel mileage of the car......

You could indeed open a second Fuelly account for when you tow, if you really wanted to keep track of those fills.......

How do you know what your average speed is per fill, GPS I am assuming?

[Pu241]

No, I prefer to keep all of the data.
That way we know what effects various conditions (low tire pressure, towing trailer, taped wheel wells, etc) have on mileage.
Additionally, I just prefer complete real world data sets.
I could also just use this car for commuting to/from work, but that's not a real world either.
The 39 MPG was a real data point and we have a good idea why I got what I got.

I'm interested in your 51 MPG, do you think the semi drafting had that much of an effect?

Yes, GPS provides that average speed data.
I was surprised at those average speed numbers, as my daily commute is 140 mile round trip most at a target speed of 60 mph, on an interstate with a posted 65 MPH limit.
But the few miles of off ramps, stop signs, stop lights, 10 mph parking lot speeds affects that average more than I'd have thought.

[bhazard]

When I had a 52.9 mpg tank with my b3 it was drafting semis on the interstate at 60 mph. Drafting helps a ton, though its not the best thing in the world to be doing.

[bhazard]

After reading this again, I need to correct something.

My Odo is reading about 2.5% higher than my GPS.
Example:
GPS = 100
Odo = 102.5

I could legitimately use my Odo for MPG calculations!

Pretty possible, I mean we do drive some cheap cars, we dont exactly have certified calibration police speedos.

[Darlo]

Yes that 51mpg was probably due to the bit of drafting, although I was not very close, but it still had an effect.

I totally understand what you mean about keeping all the data, in fact I once did a multiple regression model for my 05 Toyota echo, which told me exactly where mpg were affected most.......I will post that if you are interested.

I more ment for the purposes of our little "battle", it may be unfair to include the towing, as I will not ever have a data point that includes towing.......thats all........ (As a stats dude, it would be hard for me to cherry pick my data too, lol)

Let me know if you want me to post my regression model.

[Pu241]

Yes, very interested if statistically we can identify what cause and effect are on MPG.
Was thinking to just PM me it, but this thread is about how we can max our mileage as much as it is about ore "battle".
I look upon the statistics as another tool in reaching that goal.
I would have thought you'd of had to have separate sets of MPG data under different conditions to apply multiple regression.
Anyway I'm here to learn!