the time. >> danny and mickey set about getting the mothballed challenger 2 ready to run the bonneville salt flatsto itself, so when we're talking about of salt, this is it right here. here's a chunk. >> that's the surface? >> that's the surface. now running at bonneville is the same as driving on slushy snow. that's how slippery it is. >> what does it take to run on this kind of salt? >> this was a tire that goodyear designed for my dad. as you can see, there's no tread on it. tread weighs a lot, and as it starts spinning, the centrifugal force, the tire gets bigger and bigger. these tires will grow 2 inches bigger at 400 miles an hour. >> in once race? wow. >> so a lot of really technical things that were developed just for bonneville. >> and as they prepare for the big run, danny, now 38, finds himself rebonding with his 57-year-old father. >> he'd call me at 1:00 in the morning, and he'd say, "i got this idea." he wouldn't let you sleep. >> there's another surprise call from mickey coming soon, but this one will stop danny in his tracks. >> i can't ever remember worrying about my dad. i never