Into North Dakota

I made it across the Mississippi today! Guess that means I’m in “the West.” I crossed the Big Muddy where it isn’t so big, nor so muddy, in Brainerd, MN. If memory serves me right, Brainerd is the city where Marge Gunderson is from in the movie Fargo.

Well, put a physics teacher behind the wheel of a car for hours a day, provide him with a Scan Gauge II, and you’re bound to come up with statistics on gas mileage. Scan Gauge will tell you any engine error codes, but in addition it provides real-time gas mileage values. Driving my 1999 Saturn SW1 with the air conditioning on uses 17.2% more gas. Driving at 65 MPH compared to 55 MPH uses 22.3% more gas. Of course, this is where the challenge arises: Today I’m trying to cover 518 miles. If I drive 55 instead of 65, it will take me 1:27 longer (9:25 vs 7:58). What do I care more about, future generations having gas or my time? (Is that a loaded question, or what?) I’m glad I installed cruise control on the car, because this sure makes it easier to drive 55. I’ll probably set it around 57 today.

Remember that the shape of the car determines its air resistance, which has a lot to do with the change in mileage at higher speeds. My wagon is fairly square in the back, which is not a very aerodynamic shape.

Today’s experiment: Driving with the windows up vs driving with the windows down.

One other thing I noticed about driving 55 vs 65 is how much faster 65 feels. 55 feels like plodding along, where 65 feels zoomy. Of course, the speed limit on the Interstate I’m now driving on is 75!! It’s no wonder 55 feels safer when you compare stopping average stopping distances: 50: 175 feet; 60: 240; 70: 315. The change from 50 to 60 MPH creates a 37% increase in stopping distance!

I got in another 400+ miles yesterday. Since today I’m going to try for 518, making it to Winnett, MT, I’ve got to get going quick.

Lee