All teams used Dallara IL-02 chassis, which was fitted with a new wing package,[1] as well as unbranded TWR engines and Firestone tires.

In his second season in the series, Alex Lloyd became the runaway champion with Sam Schmidt Motorsports, clinching the title with two races remaining at Infineon Raceway in Sonoma.

Aided by an expanded schedule, Lloyd won eight races including the Freedom 100, and became the third driver to reach that number after Paul Tracy's nine wins in 1990 and Moore's ten wins in 1995.Japanese driver Hideki Mutoh, driving for the returning Panther Racing and backed by Honda through an association with Super Aguri, finished second in the standings despite missing the final round due to his IndyCar debut.

The car counts increased dramatically as a result, with 25 entries for the Miami 100, a first for the series since 1998, and a record 24 drivers at the Freedom 100.

The Liberty Challenge at Indianapolis was split into two shorter races, and the round at Watkins Glen was also converted to a double-header format, with Mid-Ohio being the only single-race road course.