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Old 08-14-2013, 06:18 PM   #1 (permalink)
bwilson4web
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Location: Huntsville, AL
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Stupid driving stunt (1000 miles on 1 tank - 2010 Prius)

Hi,

Recently, I wasted 45.5 hours between July 3 and July 21 to burn 10.9 gallons:

Wasted because I knew the car could easily achieve 1,000 miles on a single tank. But thanks to our Japanese Prius friends, I figured out how to do it while commuting to work and the ordinary chores around town.

The full write-up is over a PriusChat but the technical details:
  • Route planning - so I could avoid traffic or allow it to pass me without causing a big stink.
  • Cruise control + shifting into "N" - an energy management scheme, my feet stay on the floorboard while racking up the miles.
  • Minimum 1 hour on each trip - the Prius just gets warmed up in 20 minutes. Extending every trip to one hour achieves very high mileage . . . at the waste of driver time.
  • +99.9 MPG loop - part of route planning, I identified public road loops where I could 'do laps' at over 99.9 MPG.
My one screw-up was I filled the tank with the nozzle upside down which gave me only a partial fill. I only burned 10.9 gallons and know a proper fill would have given another 1.2 gallons, ~130 miles.

The trick our Japanese friends taught was to break a marathon into smaller bites. So instead of my typical one hour driving each day, I averaged three hours per day including the weekends. I simply incorporated the additional driving needed to reach 1,000 miles on one tank of gas. Marathon driving is not about getting somewhere, it is about putting the maximum number of miles on one tank even if it means 'doing laps.'

BTW, I know this is accurate as I use both GPS and mile markers to verify the odometer and trip meter distances are accurate to less than 1%. So too is the indicated 91.8 MPG. It turns out the original tires are ~5% too small and that screws up the indicated mph, MPG, and miles. My replacement, Sumitomo T4s are right on the numbers as are the mph, MPG, and miles.

I'm hoping more Prius owners will replicate this approach so doing 1,000 miles in a Prius is common and for us unexceptional. Personally, it is one long boring slog relieved only by having iPad music and podcasts. I've tried to cover all of the technical details in the PriusChat thread but if there are any questions, feel free to ask.

Bob Wilson

ps. I don't think there is much operator skill as much as the excellent engineering that went into the Prius. I mostly just kept it on the road and paid for the gas . . . enough for 11 cuppa coffee from Starbucks.

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2019 Tesla Model 3 Std. Range Plus - 215 mi EV
2017 BMW i3-REx - 106 mi EV, 88 mi mid-grade
Retired engineer, Huntsville, AL

Last edited by bwilson4web; 08-14-2013 at 06:26 PM..
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