Filling Gas Tank

[VetteOwner]

Originally Posted by rGS

I use a small notepad to write down things like date, time, odometer reading, tripmeter reading, and location. At the gas station, I stick the gas nozzle into my gas tank, pull the trigger, set the trigger lock, then while the gas is being pumped, using the data on my notepad and the calculator feature in my cell phone, I'm already calculating the number of miles I drove and waiting for the pump to finish pumping to enter in the number of gallons used to calculate the fillup to fillup overall average fuel economy. I only fillup until the first click because if I fill up with more gas, then I'd have to not only recalculate the fillup to fillup overall average fuel economy, but since I base my fuel economy calculations assuming that the fuel used since last fillup is the same as the amount of fuel I just pumped, mathematically that would make the gallons higher, therefore the fuel economy lower.

i do the same, except i just write down the necesary stuff like date odometer reading and gallons put in. (turns out i fill up twice a month)

easy to calculate mpg (the only real way to get accuarte) is to take current milleage-milleage last fill up all divided by gallons that you just put in

MPG =miles driven/gallons used

and then of couse reset the tripometer

[LxMike]

I've settled on fast till i'm about a gallon away from where i think it will stop then slow down till it stop then go one more stop and thats all.

[baddog671]

I stop on the first click unless Im very close to rounding a dollar. This way, you know exactly at what level you filled your tank to. The next time you pump gas, at the first click, whatever the pump says you pumped, thats the exact amount you burned.

[VetteOwner]

huh? all pumps pump at a different rate and depending on how foamy the gas is it will shut off at different intervals...ive noticed the pump will slow considerably down if someone is on the other side of the pump pumping gas...

[proletariandan]

I'm surprised nobody only fills 1/2 way or less to save weight...if every gallon is 6.3 pounds then (at least in my car) a 1/2 tank saves about 50lbs. Is the extra gas used stopping at the station not worth what you'd save with weight?

[VetteOwner]

ehh id rather not risk burning up a $300 fuel pump to save .05 mpg in my commute...or running outa gas cuz of my finicky fuel guages...

but someoen could do an experament to see how much it accualy drops MPG. like run 2 tanks only to half and the other 2 to full as can be. it would give a rough estimate....im gonna guess that it will be less than 1 mpg differance...

[rh77]

Originally Posted by VetteOwner

ehh id rather not risk burning up a $300 fuel pump to save .05 mpg in my commute...or running outa gas cuz of my finicky fuel guages...

but someoen could do an experament to see how much it accualy drops MPG. like run 2 tanks only to half and the other 2 to full as can be. it would give a rough estimate....im gonna guess that it will be less than 1 mpg differance...

That's a good idea -- but there tends to be more accuracy with the higher number of gallons pumped (smaller fills are usually more optomistic).

Due the wide variance in pumps and the actual amount on a given day, SG data would potentially be more accurate.

A few people could try it and we could pool the results ???

RH77

[zpiloto]

Originally Posted by rh77

That's a good idea -- but there tends to be more accuracy with the higher number of gallons pumped (smaller fills are usually more optomistic).

Due the wide variance in pumps and the actual amount on a given day, SG data would potentially be more accurate.

A few people could try it and we could pool the results ???

RH77

I did that. It's buried some where if you want to do a search. With a 15 gallon tank I did several tanks at 4 gallons, this was with Casper(or you can look at the gaslog). FE actually went down a smidgen. That was with tank to tank variance so take it with a grain of salt. The car accelerates much better but it was a hassle to fill up every 3-4 days for no significant gain in FE. YMMV

[VetteOwner]

yea cuz 50 lbs may seem like alot but in the big scheme the car weighs 3,000lbs so 50 lbs doesnt make much of a differance.... its like people who run around without a spare tire or jack just cuz it weights less than 50 lbs trying to save a tad(few drops) of gas....

[brucepick]

I quit on the first click.

BUT I fill more slowly than I used to. I don't want any splashing, especially considering the fill hose's vapor recovery system is probably vacuuming up any splashed droplets. Also the expanding-fuel thing; I fill up before I park at work so it could expand and spill over if I supe-fill it.

About the spare tire - Ha! I drive ~60 mi. each way and I want a full size spare. Also all my tools. Four times in 7 years I've used the tool kit for real jobs that needed doing. Old cars, you know. OK, I better shut up. Getting waaay off topic.