The Izod IndyCar series has been pretty much a spec series lately, with Honda providing engines for the past four years. That changes in 2012, when General Motors will start providing 2.4-liter V6 engines to the racing series.

GM has developed a twin-turbocharged direct-injection engine specifically for IndyCar that will, like Honda's engine, run on E85. Not to be outdone, Honda Racing Development will have a new twin-turbo V6 on the grid in 2012 as well.

"We are excited to have engine manufacturer competition again in the Izod IndyCar Series," said IndyCar boss Randy Bernard. "Chevrolet brings a strong passion for racing, technology, relevance and innovation, which is a great fit for our new car platform."

Above: Tom Stephens, GM vice chairman of global product operations, announces the company's return to IndyCar. Photo: Steve Fecht / General Motors