From what I remember on the documentary, the car drops 1 inch when that scene starts. This fools you into thinking you are dropping off the side of the building.
What's the drop like?
Words can't describe it, but I'll try.
You're in the car, you get whacked to the top of a building with a anti-gravity gun, the gun shuts off, the nose of the car points at the ground, you're looking straight down at the ground from a sky scraper, you fall, it feels like you're falling, then Spiderman catches you and the bad guys at the same time, and tells you to have a nice day. You'll be cheering at this point.