When they were talking they were only doing about 60mph. But you can't really tell how fast something is going by imagery, especially if it is recorded by a cheap camcorder. The closest thing you have to see in retrospect how fast they are going are the billboards and road signs. When they pass them, they're going pretty darn fast. When they hit the gas, it does sound like they are flooring it, but there still seems something fishy about it.