Tracy earned a point in the standings and has assured himself a front row position regardless of Saturday's second round of qualifying. Driving a Ford/Lola, he averaged 103.906 miles per hour around the 1.781-mile temporary street course.
"It's very important to set the fastest time on Friday as it gives you more leeway for Saturday," Tracy said. "We can now either concentrate on race setups or save tires for the race."
Title rival Bruno Junqueira of Brazil was second at 103.672 mph with rookie Frenchman Sebastien Bourdais third, both posting their times with less than two minutes remaining in the session.
Tiago Monteiro crashed head-on into turn 12 to bring out the red flag halfway through the runs.