Two months ago, NASCAR revealed a group-based format will be used in Sprint Cup qualifying for the road-course races at Sonoma and Watkins Glen, N.Y. (the second weekend in August). It's the same format used for the road-course events in the Nationwide Series.

Teams will qualify in groups instead of the traditional single-car runs held on the oval tracks. Drivers will be assigned to one of five or six groups, depending on the number of teams that practice at Sonoma. Group assignments will be based on practice speeds, from slowest to fastest.

Each group will have a set period of time, in which drivers can complete their qualifying run. The group's time begins when the first car receives the green flag at the start/finish line. A driver's fastest lap will count, and the starting field will be determined by overall qualifying speeds.

"I've been hoping for this qualifying for quite some time," said Greg Biffle, who won last Sunday's race at Michigan. "I loved it in the truck and Nationwide Series when I did it there. It's almost like it's less pressure on the driver, because you're not going out there by yourself, one lap, don't get a tire off anywhere. You've got to make a perfect lap. This gives you an opportunity to make two laps, typically two laps. The tires are falling off by the third lap."

Sonoma also will mark the first race for the Gen-6 on a road course. The new car is faster and has more downforce and better grip than the previous car, which was used from 2007-12. Teams are not quite sure how it will adapt to road-course racing.

"It's kind of odd because we never know what to expect with this new car," Biffle said. "It always kind of brings new things when we go to racetracks we haven't been to yet. I definitely think this car has a much better opportunity to pass, simply because we're allowed camber in the rear axle housing now, which we never had before. So it gives the car a little bit more rear grip.

"It should make for handling a little bit better, so maybe some more side by side, maybe some more passing. Though road racing inherently has been tough to pass. because everybody slows down at the same point to go around the same corner. So I think this car could definitely promote more passing and better racing because of the attributes it has over the old car."

Last month, Richard Petty Motorsports drivers Aric Almirola and Marcos Ambrose tested at Sonoma for two days, familiarizing themselves with the Gen-6 on this course. Ambrose, who excels in road racing, is one of the favorites to win Sunday's 110-lap race at Sonoma. The Australian has finished no worse than eighth in the last four events here. His two career Sprint Cup wins have come at Watkins Glen (2011 and '12).

"We know the two road course races are easy targets for us," Ambrose said. "We have struggled at Sonoma the last couple of years, and we wanted to go there to get a check on this new car, to try to dial in the racetrack.

"It was good to go out there. It was very expensive to go out there. It took a lot of commitment, a lot of time away from the workshop, a lot of time away from our weekly schedule. To travel the truck out there, rent the facility was not cheap. It was a big commitment to do it."

Jeff Gordon has the most wins at Sonoma with five, but Gordon's last victory here came in 2006. There have been no repeat winners in the last eight races at this track. Clint Bowyer is the defending race winner.

"Hopefully, we can do it again," Bowyer said. "It's always nerve-wracking just getting on the racetrack, shifting gears and having to down shift coming onto pit road to meet pit-road speed. It's exciting, and the track itself is fun. I think it's like a short track of road-course racing."

Danica Patrick is expected to make more series history. No female has competed in a Cup race at Sonoma. Patrick is quite familiar with this course. She made seven IndyCar starts here, with her best finish of fifth coming in 2008.

"It's going to be challenging," Patrick said. "Stock car drivers just don't get a lot of time on road courses, and I've spent my whole career for the most part doing it. It's nice to go to a place where I feel comfortable I suppose."

Forty-three teams are on the preliminary entry list for the Toyota/Save Mart 350. Three drivers -- Alex Kennedy, Victor Gonzalez Jr. and Paulie Harraka -- will attempt to make their first career start in the series at Sonoma. The last time three or more drivers made their Cup debuts in the same race was on Oct. 24, 2004, with Chad Chaffin, Mario Gosselin and Travis Kvapil making their maiden starts at Martinsville.

Series: NASCAR Sprint Cup. Date: Sunday, June 23. Race: Toyota/Save Mart 350. Site: Sonoma Raceway. Track: 1.99-mile road course. Start time: 3 p.m. ET. Laps: 110. Miles: 218.9 (350 kilometers). 2012 Winner: Clint Bowyer. Television: TNT. Radio: Performance Racing Network (PRN)/SIRIUS NASCAR Radio.