Originally Posted By: buster
Take the Honda Accord Coupe for example. If they were able to make it 300-400 lbs lighter, I'm curious as to what the fuel efficiency would be?
I'd venture to guess it might improve the fuel economy by about 1MPG city, with a lesser improvement for highway.
There was a DOS program called, I believe, CarTest which ran calculations based on vehicle weight, engine size, frontal area, etc. to both come up with the expected 0-60 and 1/4 mile times as well as estimated fuel economy. It was very accurate. You might try finding it to play with it to see what it would take to make a 150MPG vehicle.