When drivers career around the Indianapolis Motor Speedway on Sunday, they'll push the pedal to the metal and reach speeds of more than 200 mph.
It will be race day as usual -- except for one key aspect: For the first time in four decades, the single-seat cockpit cars will be powered by a new fuel.
Gasoline has long since come and gone at this raceway, but now the Indy Racing League -- the sanctioning body of the racing series -- has added ethanol to the mix.
This year, the cars will run on a blend of 90 percent methanol, which is distilled from wood, and 10 percent ethanol, the alcohol fuel made from the sugars found in corn.
"We have not lost any speed," said Jeff Horton, the league's director of engineering. "Cars don't smell differently, and in reality, there's no detectable difference."
The league's transition toward greener fuel has thrilled renewable energy advocates who hope that this coming-out party will raise awareness of the benefits of bio-fuels. Critics, however, say it is a mistake to expect that corn could be the answer to America's future fuel needs.
The racing league is moving ahead with the homegrown fuel, though. In 2007, the cars will run on 100 percent ethanol power.
"It's one part publicity and one part showing our efforts at being responsible in using alternative fuels," said John Griffin, the league's vice president of press relations. The U.S. Office of Energy Efficiency and Renewable Energy says that ethanol is clean-burning and that using it instead of gasoline cuts greenhouse gas emissions by 18 percent to 29 percent a gallon.
Griffin also stressed that embracing ethanol -- the product as a fuel source and the industry as a sponsor -- highlighted the league's ongoing role as an innovator.
"We see ourselves as leaders in safety and technology in motor sports," he said, citing the example of the new safety barrier around speedways, which was first used in the Indy series.
The league's interest in a cleaner fuel option came long before President Bush's request to have the nation quit its addiction to oil.
Four years ago, Indy series driver Paul Dana, who was killed in a crash earlier this year, touted using ethanol as an alternative fuel, and testified in Congress last March.
Dana's efforts have paid off, and Tom Slunecka couldn't be happier.
Slunecka, the executive director of the Ethanol Promotion and Information Council, believes 100 percent of the Indy 500 cars running with 100 percent ethanol legitimizes the pumped up grain alcohol as a fuel for America's cars.
"To have the IRL [Indy Racing League] come forward saying this is high performance fuel says volumes," Slunecka said.
The higher octane content in ethanol allows cars to reach even greater speeds. IRL cars race at more than 220 mph, which is the equivalent of crossing a football field in one second, he said.
Slunecka also hopes that the Indy 500 publicity will raise consumer awareness and inspire people to turn to ethanol-enriched fuel. The ethanol council argues that ethanol is not only right for the environment, but that it will be a boon to the U.S. economy.
Because ethanol is made from corn, American farmers and producers would reap the financial rewards of the nation no longer relying on foreign countries for fuel.
Not everyone is convinced.