Fresh from his win at Pocono last weekend, Biffle proved the benchmark for single-lap speed around the 2.5-mile track, leading both of the day's sessions, which served to prepare both qualifying and the race, as there will be no further practice before Sunday's 90-lap event.
"I feel like our simulation is better and we are showing up closer when we unload at the racetrack," said Biffle following practice. "I just have to keep it on the track. Keep the gearbox in it, keep the brakes on it and not make any mistakes on pit road.
"The cautions have to fall right for us too and we need fuel mileage. Everything is a factor when it comes to the race on Sunday, but we have a good car to start with."
Juan Pablo Montoya was second fastest in the final session, where most drivers ran qualifying simulations ahead of Saturday's fight for pole position. The Colombian ran solely in qualifying trim, completing only two flying laps during the hour and 20 minutes of practice.
However he was unmatched for consistency in race trim in the first practice session of the day, although others like Australian Marcos Ambrose would prove just as quick over five-lap runs in the cooler track conditions of the final session, which he finished third fastest ahead of Kurt Busch, points leader Kevin Harvick and five-time Watkins Glen winner Tony Stewart.
The Hendrick Motorsports drivers struggled with balance throughout the day, reigning champion Jimmie Johnson spinning early in the first session and finishing the day 13th fastest as the best from his outfit.
His team-mate Jeff Gordon also fought a loose car, an impression he confirmed by allowing standby driver Scott Pruett to complete a few laps in his #24 Chevrolet, as the four-time champion's wife is expecting the couple's second child soon.
Qualifying will take place on Saturday morning ahead of the Nationwide Series race.
