I've had this talk with alot of people over the course of my driving years, and I'm sure some of you have wondered this as well.
If you go slow, everyone knows that you use less gas than going fast. The faster you go the more gas you burn. I've even read that you add the equivalent of 20 cents per gallon for each 5 miles per hour you drive over 60 mph.
That being said, if you're driving faster you get to your destination faster. So, my question is, are you consuming relatively the same amount of gas by going faster thus reaching your destination sooner? Or do you still lose gas by going faster? If you increase your speed you'll get to your destination quicker. So, the question is, is the speed vs. time vs. mpg relatively the same as it would be if you were going slower?
I'm making these numbers up unless I have an equation next to it:
Say you burn 20 mpg going 65. Your trip is 20 miles, so you burn ~ 1 gallon of gas. You make the trip in about 18 minutes, 30 seconds ( (20 miles/65 mph)*60 min/hour).
If you increase to 80 and make the trip in 15 minutes, then are you still consuming the same total amount of gas?
I realize lower rpm's burn less gas, but in terms of speed alone.