Last to go in the new single-car qualifying format, Tracy claimed the provisional pole with a time of 37.006 seconds (115.960 miles per hour) for a circuit record.
Cool conditions and strong winds have kept the times slow, but Tracy believed he could have achieved a better mark.
"I kind of messed up a little bit," he said. "I thought I had another timed lap. I wasn't really counting the laps, and I wasn't really listening either. I really ran it hard on that lap, especially through the (S turns). That's where I made up the time."
This was the first single-car qualifying session on a road course in the 25-year history of the series. Due to the short length of the track, CART officials elected to make the provisional qualifying session on the 1.2-mile course single-car format. Each driver was allowed four times laps in addition to an "in" and "out" lap.
Tracy has dominated the series, winning all three races. Saturday, he locked up a front row starting position for the fourth time in as many opportunities.
"It's good because it takes a lot of the pressure off," Tracy said. "We can now concentrate on improving the car."
Brazil's Bruno Junqueira was second in 37.022, missing out on the provisional pole by just 0.016th of a second. He has finished third in two of the three races this season and is second in the standings.
Qualifying for Monday's race continues on Sunday.