He contested 28 races, before he was replaced midway through the 2007 season by Sebastian Vettel.
Speed later turned his career towards stock car racing; specifically NASCAR, where he drove for Team Red Bull, Whitney Motorsports and Leavine Family Racing in the Sprint Cup Series.
Subsequently, he moved into Global Rallycross with Andretti Autosport, winning the title in 2015, 2016 and 2017.
On November 1, 2018, Speed announced he would be joining Subaru Rally Team USA for the 2019 ARX season.