. >> three days after my worst day in my life, my dad got a call from michael andretti asking if i'd be interested in driving for his team. >> andretti is one of the biggest names in racing. to be asked to join his team as an adult is an honor. to be just 15 at the time is incredible. >> it takes a lot of talent and hard work. you know, when you start in karting, you spend your time learning, developing your hand-eye coordination and the mental skills it takes to drive a racecar, because when you're out on the track, you're thinking about where you should brake at. 'cause we have brake markers that are 100 yards, 200 yards, and you're thinking about when should you turn into the corner, and on top of that, you're thinking about where the other cars are on the track and what the car's doing so you can relate that information back to your crew and they can make the car go faster. because, really, everybody's got the same equipment, so at the end of the day, it comes down to whoever can drive the course the best and whoever's got the best car. >> so, what's zach's secret to success? >>