Quote Originally Posted by Atlblkz06
* Use the A/C instead of rolling the windows down. The drag caused by the windows slows you down and affects your too. When your motor is working (not idling), the A/C power draw isn't all that significant and will probably cost about the same as the drag from the windows (I cant prove this, just my theory).
This was on an episode of MythBusters and they proved it to be true.