Method 2: Driving with the windows down (and blasting A/C)
Temperature change in first 10 minutes: 2.5 degrees/minute
For day two, I did what I assume most people do when they're getting into a hot car: I rolled the windows down, hit "MAX/AC," and drove off. The cabin was cooler than the previous day, at only 126 degrees. I rolled the windows back up after two minutes, and by the seventh minute, the temperature was down to 110 inside the car. It was down to 101 by the time 10 minutes had passed, and after 15 minutes, it was down to 97 degrees. That's a full eight-degree advantage over the control.
Method 3: Driving with the windows up (and blasting A/C)
Temperature change in first 10 minutes: 3.1 degrees/minute
On day three I hit "MAX A/C" and drove off, but kept the windows up. The car's temperature went from 138 to 122 after five minutes, to 107 after 10, 94 after 15, and ultimately wound up at 88 degrees by the time 20 minutes had come and gone. I know what you're thinking. It's somehow faster than opening the windows?!? Well, that kind of makes a lot of sense. When you open your windows, you let plenty of heat out, sure, but you also let out plenty of that blessed, blessed cold air. It more than cancels out, and you don't effectively start the cooling process until later.