It was doing something new: Putting its top engineers behind the wheel of cars for close-up assessments, said U. S. auto giant General Motors Co.

The Detroit Free Press reported on Thursday that GM North American President Mark Reuss called the new program "knothole drives," as in the engineers would be testing cars to such a degree that cars in development would pass through what Reuss called "a small knothole of excellence."

Vice Chairman Tom Stephens said before a test run that would include the Chevrolet Cruz and a stint behind the wheel of three rivals, including a Toyota Corolla, a Honda Civic and a Mazda 3, "This is the fun part of what we do."

He said, "This is why I went to engineering school."

After a few driving runs around Ann Arbor, Mich., a team of engineers, the so-called Knothole Gang, had formed opinions on the Cruz, including pros and cons.

Stephens further said, "We just need a couple of more things and we'll be best in segment." (With Inputs from Agencies)