Zero to 120 MPH in four seconds and then it climbs 420 feet. This video really doesn't do the well-named Top Thrill Dragster justice. The whole ride takes 17 seconds.
Sometimes the train doesn't quite make it over the top and the have to crank up the speed a little bit and try again. A few years ago a train had the pleasure of having the exact weight and friction to get it stuck up on top of the track, 420 feet in the air, for seven minutes until an employee could get up there and give them a push.