Is it supercharged or naturally aspirated? I used to have a 1997 Grand Prix with the 3.8 supercharged engine, and would regularly see 31-32 mpg on highway trips without trying. The supercharged cars had a 2.93 final drive ratio compared to the NA's 3.29, so I guess that helps when you are not getting on it all the time.
Edit: Just read that you were going to Berkeley Springs, WV. I used to live there! A nice little town, and tons to do in that area if you are into outdoorsy type stuff. Head down to Seneca Rocks and Dolly Sods (a few hours away) if you are going to be there a while. Beautiful area.
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