 Honda also came to the IRL in 2003, and by 2005 was clearly the dominant engine manufacturer.After Chevrolet and Toyota elected to shut down their IRL involvement after 2005 season (Chevrolet temporarily hiatus from IndyCar Series for six years while Toyota USA elected to focus on NASCAR involvement), Honda became the only standard spec-engine manufacturer in the IndyCar Series starting in 2006 and continued in that capacity through 2011 as it was announced by Indy Racing League president & chief operating officer Brian Barnhart and Honda Performance Development president Robert Clarke on December 15, 2005.The Honda Indy V8 engine was partnered and co-developed by Ilmor, which is part owned by Roger Penske for tune-up, engine maintenance, arrangement and trackside support.