Simply type in one of the following names at the driver creation screen to unlock their car in any game mode:
Audrey Clark
Benny Parsons
Buster Auton
Cheryl King
Chuck Spicer
Crissy Hillsworth
Daryl Wolfe
Dave Alpern
Dave Nichols
Diane Grubb
Dick Paysor
Jim Hannigan
Joey Joulwan
Josh Neelon
Katrina Goode
Ken Patterson
Kristi Jones
Mandy Misiak
Michelle Emser
Rick Edwards
Rick Humphrey
Sasha Soares
Scott Brewer
Tom Renedo
Traci Hultzapple
Troi Hayes
To see the Bonus Championship FMV about Richard Petty you must win 8 championships.