540 Miles out of last fill up!

Congratulations. It is always fun to break a personal record.

Your post is more suited for the Gen II Prius Fuel Economy forum. The competition is great here on Prius Chat as you can see here; priuschat.com/threads/my-first-712-miles-per-tank-of-gas.114725/#post-1636480

The Gen II drivers have had a long time to compete in all the MPG games.

 

For some reason the tune of Rudolph the Red Nose Reindeer came to mind when reading the end of your post.

Prii-V the wagon hybrid
Had a very big hatch back
All of the other Toyo's
Used to laugh and call him lame
Then one foggy Weekend morn'
Coach B came to say
Prii-V with your Trunk so big
Won't you haul my team tonight?

... will have to finish later, back to work ...

 

Get yourself a V and you might be able to break 600! I got close...Thought about pushing it a bit more. Filled up with 10.682 gallons....so I'm thinking I might have made 600. Weird thing was when I was down to my last 10 miles in range, I was in electric mode most of that time, but it still kept ticking down the range like I was using gas. Who knows what kind of formula they use to calculate that.

oh, my empty tank indicator came on at 565.

 

Did you notice that your last 5 bars of gas went alot faster than the first 5?

I tend to fill up when the price is 3.75 or less around here, i don't care how many miles i have on the tank.. but when i was waiting out some temporary price gouging on my last tank, I noticed that I got like say 340miles on the first 5/10 bars of gasoline. Then over the next 60 miles the next bars 6 and 7 also disappeared while my average MPG's stayed the same on the computer. I ended up filling up at 402 miles with 3 bars left, but it just seemed like the 2nd half of the tank was going faster than the first even though my computer's average MPG was staying constant.

 

If you determined you were in electric mode by the in-dash display of mpg (goes to the top in US?), it can be deceptive.

On our Canadian liters/100km setup, normally if you're using no gas the consumption bar graph drops to the bottom. And it's true at lower speeds, but above a certain speed threshold the engine continues to idle, as evidenced by a ScanGage, even though the bar graph is showing bottomed out. ScanGage will show somewhere around 900~1000 RPM.

 

The gas gauge is NOT linear. My understanding is that it is PURPOSEFULLY not linear.

 

I always get more on the top half of the tank too. But then again, I usually get around ~140 miles before even the first pip blinks out. Then curiously, my 2nd and 3rd pip from the bottom usually net me a lot of mileage.

Heck, I'm just happy I'm no longer dealing with the bladder effect that I had on my '08 Prius.

 

I only get around 300 to a tank how in the world did you get 500

 

I presume the gas gauge and the top half being longer than the bottom half has a lot more to do with the fuel tank shape... then whether or not the gage is linear or not. Most gages that I've seen on the inner workings - are linear - in that they are a radial arc - with a float arm much like your toilet has for filling it's tank. it's just connected to a poistion sensor in this case... the thing is - now that tanks are plastic - they can pretty much make whatever shape to fit contours of the car, tuck over frame rails, etc.
my wife's mini van as an example has a tank that looks like a mushroom - wider at the top then it is at the bottom...

well, so the gas gage measures vertically... right ... so if the top half of the tank if longer and or wider - it has more surface area - or more accurately - more volume per given height then the lower half of the tank ...

so - simple math right - essentially we have a 2-stage tank ... the top half is dimensionally bigger than the bottom half -
thereby has more volume than the lower half... so it would take longer to consume the top half of the tank - as the gage gets lower (because the tank is theoretically level) ... there reaches a point where it crosses over into the smaller portion of the tank - and appears to consume faster --

in reality - you are consuming gas at the same rate - say it's 40mpg... or 1.3 gal/hr something like that -- anyway - point is .. the resovoir you're pulling from is changing - not the consumption rate.

think of it like a margarita glass... that last swallow is a thimble down at the bottom - but a huge soup bowl at the top... can't think of any other good anologies...

 

Since the gauge is digital, they can easily correct for tank shape. My understanding is that they do, and THEN they make it non-linear.