Official: What are your real world MPG Numbers
- Thread starter Sonic-Mike
- Start date
gdideric
New member
If you start with a full tank, drive and then refill the tank, you can only put in what you took out...so whatever you put in, is what you took out.
you haven't burned the fuel that is still in the lines and the tank, so it doesn't go into the MPG calculation. You only count the fuel you don't have any more.
firstorbit84
New member
You fill tank all the way, set trip odometer to 0 (I also reset the car's mpg computer at this point to compare), and then drive. Then, when you get low on fuel, fill tank all the way again and divide the number of miles on your trip odometer by the number of gallons shown on the pump. Reset trip odometer and repeat.
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2012LTZ
New member
.000001 accuracy? Give it up. I did.
The sonic fuel neck is pretty good about stopping when it's totally full.
I can only get a short squeeze or two after that.
Plus, your mileage will vary so using averages is going to give you the clearest picture anyways.
I'm showing an average of 31mpg with 2 miles city, and 19 miles highway one way. But coming home, 1 mile of the highway is bumper to bumper and the 2 miles city I hit every light.
I have the 1.4T with auto.
I used to drive a Jeep Cherokee so just think how happy I am at the pump!
I have the 1.4T with auto.
I used to drive a Jeep Cherokee so just think how happy I am at the pump!
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RichieRocket
New member
Bogus, a single tank mpg is definitely not 100% accurate. I try to be consistent, let the pump nozzle shut off, then again at half-squeeze. But if you use different pumps at different gas stations, the shut off points can be different. You can run some estimated numbers to see:
350 miles on 10 gallons, assume shut-off varies by 0.25 gallons.
So if it shuts off early 350/9.75 = 35.9mpg
Topped off 350/10.25 = 34.1 mpg
If you are consistent in the original fill-up and the after fill-up, the error will be small, less than a percent.
This error drops when averaging over many fill-ups, I have 62 fill-ups in my average in the Fuelly banner below.
At the Green Grand Prix, a competition at Watkins Glen Raceway, they measure fuel by a before and after weigh in.
Welcome To The Official Green Grand Prix Web Site
"Other vehicles will be weighed immediately before and after the rally to determine fuel use."
GeneralZod
New member
Don't waste your time. Most of those systems cost too much upfront or in the back end. Your hydrogen production is way to slow unless you use massive amounts of power and really good systems. On the car or truck systems are smoke and mirrors.
Hook a 9v battery up to some wires and see how much HHO you get. It isn't much even after hours. Try it for days... Then think about the load on the alt.
Cutting gasoline with water is just asking for trouble. It was also a trick used in WWII in prop fighters. It was only use for short amounts of time. It required a whole injection system and methanol. Overuse causes major internal failure and those engines were built for that type of use.
Again, these costs would never be paid back.
Doing things like going to 185 size tires would have a larger impact for the cost and amount of work. My LTZ has 205s, and I know I would jump at least 4 MPG with that switch and a LRR tire. I just don't want to do that.
Now, I am itching to lower the car. Just trying to figure which route. That will also create gains. However, it takes a long time to get back that 300 bucks. I would be doing it for handling and looks with the added benefit of more MPG.
If you can make free aero mods, those will give you some increase. Also, removing excess weight will have some major increases. Even on the highway (inclines).
The largest improvements can be made by the driver. Foot off the gas and don't use the brakes.
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GeneralZod
New member
Think in terms of 3 and 5 tank averages. It takes more of the wiggle room out.
RichieRocket
New member
Good point! When I used to keep my own mpg spreadsheet, I tracked a "5 tank rolling average"
I have a Fuelly 'mini-stat' set for average mpg over the last month, that will give 3-5 as you mentioned. That's a good look at how things are trending.
yevgenievich
Member
no drafting on purpose to get ~47mpg, light on the throttle, speed up by 5-7mph on downhills for upcoming uphill slow down by 5-8mph . I tried to stick behind couple of trucks and the average started going up, indicating ~50mpg or so. Checking at the next fill up manually came up with 46. something mpg. Usually around city i can get ~44 if light traffic trying to coast as much as possible through lights and take corners without slowing down much. After tune will probably be worse mpg
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GeneralZod
New member
Hand calculate to see if the DIC is accurate. Mine is normally off around 1-2 MPG. Some have said it could be more. Also, if you are hypermiling, I wouldn't say you are going 75+ MPH.
Even my SGII was off when I hypermiled my TDI. It was around 4-5 MPG. If I didn't hypermile it was almost dead on.
GeneralZod
New member
Those tank averages take out the freak tanks high or low. It is also a great indicator of how the car performs in certain weather conditions. This method will help with justifying grille blocks and so on.
Just be empirical, and do one change at a time. It drives me nuts when people test trying eight things at a time. You can't pinpoint a successful method or one that is not.
Mild hypermiling had the biggest improvement overall. I have said this before. You can ruin a tank average, and even a monthly average on a cold morning. Hypermiling can deflect this issue.
getting about 29 mpg city driving
40mpg on 55mph highways when im going 65 or so mph mostly
35mpg on 70mph highway when im going 75-80mph mostly
when my dad drove the car on a 500 mile road trip ( he drives like a grama) he got 45mpg average doing about 65 mph for 300 miles, and 55mph for 200 miles.
also i have think my mpg gauge is a little off, it seems to read aboud 2-3 mpg better then what im actually getting
40mpg on 55mph highways when im going 65 or so mph mostly
35mpg on 70mph highway when im going 75-80mph mostly
when my dad drove the car on a 500 mile road trip ( he drives like a grama) he got 45mpg average doing about 65 mph for 300 miles, and 55mph for 200 miles.
also i have think my mpg gauge is a little off, it seems to read aboud 2-3 mpg better then what im actually getting
RoXXXanne13
New member
1.8 5spd i get about 27 city, a LOT of stop and go heavy traffic to and fro work.. 34-36 highway depending how fast we go i usually go 305-310 miles on a tank. however, trips to NY and back to NC going 75-85mph 3k-3500k rpm get about 34. 65-75 2800-3200 ( roughly ) we get 36, last trip i held steady at 71mph and got 36.4mpg cant complain
Maddog2020
Active member
New Personal Record!
I filled up right before entering the Florida Keys. The speed limit is 45-55 with few lights. These are ideal conditions for good gas mileage. I broke my previous record of 45 MPG without a tune. I had select-a-tune set for stock.
501 milles
10.847 gallons
51.6 MPG on DIC
46.2 MPG calculated (off by 5.4)
I filled up right before entering the Florida Keys. The speed limit is 45-55 with few lights. These are ideal conditions for good gas mileage. I broke my previous record of 45 MPG without a tune. I had select-a-tune set for stock.
501 milles
10.847 gallons
51.6 MPG on DIC
46.2 MPG calculated (off by 5.4
)
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2012LTZ
New member
a bicycle.
...just kidding but not really.
I love the tropics.
BTW, those gauges are all out of whack more than most of you guys would prefer. ...and when the UG goes bad, the data you start getting starts at bad then goes to nonsensical. Still love mine and will be super handy for numbers if I try sticking a hydrogen generator or something on my car.
501 milles
10.847 gallons
51.6 MPG on DIC
46.2 MPG calculated (off by 5.4
Way to go Maddog! ( I spent about two years of my life finding a way to buy a bottle of that stuff nearly every night and probably responsible for many of the weird stories I have )
You can never tell who's behind these kinds of forums or who may be their sugar daddy or billionaire suitor. Nobody touched THIS post so I'm inclined to believe it's taboo here. I swear when I built my solar array, all of the guys operating the forum were I went for help were oil guys, or guys heavily invested in oil. I was discouraged the whole way along, them telling me what I was doing wouldn't work, wouldn't have a positive roi. ha. There were even users there that called them on it from time to time.
Nevertheless, when\if I get the time\money, probably spring, I'm going to build one of those contraptions and come back here and .