They look like one-person bobsleds. They run on lawnmower engines. And they get incredible mileage.
They’re cars that achieve what’s called supermileage. College engineering students from as far away as Quebec come to compete in the SAE International Supermileage Competition.
It’s held every year at the Eaton Corporation Proving Grounds in Marshall, Michigan.
When we visited last week, a lot of the students were scrambling to finish last-minute improvements to their vehicles before the moment of truth.
Each driver had to complete six laps on a 1.6 mile track. And they had to maintain an average speed of 15 miles per hour. Teams could do as many runs as they wanted.
Laura Pillari is the driver for the University of Michigan team.
"I was a little nervous because there's a lot of stuff to do with my hands, and I'm kind of crammed in there with this little helmet, and it's very, very hot in that car in the sun."
To measure mileage, competition officials gave each team regulation fuel tanks that were weighed before and after each run. These vehicles can get hundreds or even thousands of miles to the gallon.
Most of the teams build their cars out of fiberglass, but carbon fiber is the ideal material for teams with enough experience and resources. It’s extremely sturdy and lightweight.
Jim Gluys is an engineer with the Eaton Corporation. The company sponsors the competition along with SAE International.
"They go through and they highly modify the engine for one thing. They build very aerodynamic bodies for the cars, and then they employ usually what’s called a burn and coast technique."
The students say this driving technique is crucial for achieving high mileage.
John Pearson is a senior at Penn State University – Behrend College.
"The biggest thing is actually how you drive it. We run the engine up to maybe 22 mph and that takes five seconds, then we cut the engine and coast for the next two minutes, and then you fire the engine again."
Despite their amazing mileage, these super lightweight vehicles are not made for the highway. They have only 3.5 horsepower. Compare that to a typical small car, say, the Ford Focus, that has 143 horsepower.
But many team members say the competition is less about real world applications and more about giving students experience and inspiration.
Jon Hofman is a senior from Calvin College. He said it’s especially important for young engineers to value fuel efficiency.
"For a long time it seemed like Detroit didn't care about fuel efficiency, and I think we're trying to change that attitude a little bit. The new cars coming out of Detroit are more and more efficient and that's exciting."
The Calvin College team placed seventh in fuel economy with 705 miles per gallon.
The team from UM placed second in design but they did not place in fuel economy.
The top prize in both design and fuel economy went to Penn State-Behrend. They achieved 1,485 miles per gallon.
