Nascar Race Today

CONCORD, N.C. - There are five races remaining in the 2013 Sprint Cup season, but NASCAR took a major step toward next year with a test Monday at Charlotte Motor Speedway.

With a goal of engendering more passing by improving handling in traffic, six drivers representing the three manufacturers tried seven changes bundled in three configurations on the Gen 6 car, which made its debut this year.

NASCAR vice president of innovation Gene Stefanyshyn said all of the changes, which included a strip across the roof, a larger spoiler and a slightly raised splitter, could be incorporated into the cars for 2014.

"It's essentially all aimed at aerodynamics," Stefanyshyn said. "Some of the chassis changes are to bring more stability to car. Our intent is to learn as much as we can. Not everything we try will be successful. Those that work will find their way into '14 package. Those with more work will be in the '15 package. The plan is to get through this and then start turning an eye to '15."

Running laps on the 1.5-mile oval were Jamie McMurray and Jeff Burton for Chevrolet; Trevor Bayne and Brad Keselowski for Ford and Denny Hamlin and Brett Moffitt (substituting in place of Brian Vickers) for Toyota.

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Among the most promising of the proposed adjustments is the abolition of a minimum height rule, which would allow teams to keep their cars' front ends glued to the track and reduce the dependence on airflow.

The theory is that less emphasis on aerodynamics should allow more stability to a trailing car as it attempts a pass.

"The no ride-height rule is a real positive," Burton said. "There might be bigger stuff, but I think that's the best chance to have a positive with no negative. I just think that it makes a lot of sense being able to hold the ride height more stable and more secure. I don't think it's night and day on the track (and) going to be some crazy difference in how you drive behind other cars, but a little bit here and a little bit there adds up."

Penske Racing director of competition Travis Geisler said other changes aimed at minimizing drag and improving downforce also should help with passing.

"The trail car is at such a deficit," Geisler said. "You hear all the drivers refer to what they say is a wall they try to pass somebody on the straightaway. What they've come up with, you're not going to have an advantage, but you're at least not going to have the disadvantage that you've had. Hopefully that will take care of it.

"I know all of us want to see more passing for the lead. That's what everybody comes to watch, and we're all here to do everything to try to make that a reality for us. Our cars are much more equal than what they used to be. When a car is out front, the biggest difference between them is position in the air. To overcome that, you're going to have to defy physics a little bit. You're going to have some trickery involved to get around it. That's what they're trying to do with some of the packages here is to really trick the system a little."

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Stefanyshyn said NASCAR was measuring several sources of data - from timing and scoring data showing passes per lap to fan feedback in social media - in finding ways to try to improve the action on 1.5-mile superspeedways such as Charlotte, which make up the bulk of the schedule.

"We're seeking the truth," he said. "We've heard some say (the cars) need to go faster, some say they need to go slower. If you listen to everybody you're going in a lot of different directions. We try to find the centroid of the opinion, look for data and marry the two up. It's never going to be 100% perfect. We do the best we can with it."