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I'm back from our trip and I have some interesting things to report. Last year I did some short distance mileage experiments with my '73 squareback, just to see what the effect of speed was on my gas mileage. You may remember that I found that I did 2 trips, each 100- 150 miles long, and measured the gas mileage on each. The first loop was done at 65 mi/hr, while the second was done at 60 mi/hr. The results were in agreement with Dave Hall's suggesting that my poor gas mileage was due to my foot, which had become heavier with age. I got about 27 mi/gal at 65 mi/hr and nearly 29 mi/gal at 60 mi/hr. These past 2 weeks I drove a different car from Madison, WI to Tucson, AZ. With a side trip to the Grand Canyon, the total trip distance was 4364 miles. On all previous trips with this car, a '96 Taurus wagon, my driving habits had been the same as in squareback trips, and the gas mileage was also about the same: 22-24 mi/gal. I tended to drive about 7 mi/hr faster than the legal limit. On this trip, I decided to see what happened if I made a concerted effort to keep my speed down, so I set the cruise control consistently for 67-68 mi/hr. Of course there were slower periods as well as occasional faster ones. I also made sure that the tires were properly inflated. The end result was that our overall trip mileage was 28.13 mi/gal with 3 tanks actually in the 30-32 mi/gal range. The overall average includes 5 days of city driving in Tucson which resulted in one tank that gave only 23 mi/gal. The whole trip consumed 155 gals of gas. Both the overall average and the individual tanks (except for the one 23 mi/gal tank) were the best figures I had ever seen in this car. The end result was that I saved considerable gasoline by holding my speed down. This was done at the expense of longer driving days, but we still made it in the same number of days (3 days each way, a bit over 600 miles each day.) Three days of driving gives one lots of time to think, and on the way home it finally occurred to me that changes in altitude should also have a considerable effect on air drag, since there is lots less air to push aside at 5000 ft. In fact, my best mileage (31.9 mi/gal) occurred traveling eastward across the high plains of Arizona and New Mexico. However, I also had a good tailwind at that time, too. All of this is enough to convince me that it would be worthwhile to plan to drive a bit slower on the way to the 2006 Invasion. I saved a bit more than 20% on gas doing this. At current gas prices, that's a lot of money and it's worth saving the gas, just because the supply is declining. We saw gas prices ranging from $3.15 to $2.73. The highest were in the mountains of Arizona and the lowest were in Nebraska/Iowa. -- ******************************* Jim Adney, jadney@vwtype3.org Madison, Wisconsin, USA ******************************* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ List info at http://www.vwtype3.org/list | mailto:gregm@vwtype3.org ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~