I wonder if a "suitcase" auxilliary gas tank would make any sense? I mean, have the regular tank be dinky and able to meet your needs for, say, a week or two of motoring. Then, when you need to make a longer trip or for some reason are temporarily putting on more miles, you stick another tank in the trunk and plumb it in via quick-connect, like you do with outboard motors.
Just don't fill the tank. run half a tank all the time.
I have the opposite problem in that I drive great distances without stopping and only have a 11.9 gallon tank and if it wasn't for my mpg boosting I would be filling up at 320 miles and I take a trip that is further than that so instead of gassing up once before I leave and once there and once back I would be gassing up twice on the way there and twice on the way back and only NJ had better gas prices CT is way higher as well is the southern half of RI. Now I have a trip to Maine 392 miles and will be out in the farm land - without knowing where the cheep gas stations are it would be nice to have another 6 or so gallons in the trunk already to get me there and back. Plus if you end up traveling late at night finding an open station can be a pain sometimes.
Blame Tango for this. He was the one that pointed out this forum on another forum. Compaq888, start adding more hundred mile intervals.
Stock 1996 VW Passat TDI. No secondary tank or other nonsense, just careful filling of the OEM stock fuel tank.
Starting 26 May, 2005 at 181,144 miles, next fuel at 182,545 miles (1401 miles). Fuel needed to re-fill: 21 gallons (US gallons) for a tank average of 66.71 mpg.
Next fuel stop at 183,919 miles (1374 miles). Fuel needed:25.959 US gallons for an average of 52.93 MPG.
2,775 miles (4466 km) on one fuel stop using 46.959 gallons (177.76 l.) at a rate of 59.094 MPG (3.98 l/100km).
I have several 900 and 1000 mile tanks from my Passat TDI sedans. I have multiple 1100, 1200, and 1300 mile tanks from my Passat wagon, but only two 1400 mile tanks.
Thing is I have this opinion (irrational?) that non-full tanks have a lot of sloshing thus increasing evaporative losses. Does the vapor recovery system recover them all anyway and put them to good use?
That's the idea - modern emissions-controlled cars are supposed to have fully closed fuel systems. Fumes in the tank are purged and burned via the evap system.
My best tank was on my temporary ride. I went 655.* miles and used 11.7 gallons. According to it's rated size(12.2 gallons), I had .5 gallons or about another 25-30 miles left. So far with the new car, I've went 433+ miles miles and used 8 gallons. At that rate, I could have went 660 miles or more before running dry.
Horsepower is how hard you hit the wall, torque is how much of the wall you take with you.