CONCORD, N.C.-- Crew chiefs and engineers are taking the yawn out of Sprint Cup testing at Lowe's Motor Speedway and putting in the yaw.
The hope is to close the gap between Roush Fenway Racing's Carl Edwards and the rest of the field at 1.5-mile tracks such as LMS.
Edwards' car, according to several crew chiefs and drivers, has been dominant in part because he has been able to handle a setup in which the rear housing is turned to the right, making it appear the car is going sideways down the straightaways.
This gives Edwards more yaw -- movement in the back end -- that creates more downforce and allows him to make a better transition going into the corners.
"I think everyone sees it, even on TV," said Denny Hamlin, who is sixth in points. "It's very, very noticeable for us drivers. To those that don't really know the nuts and bolts of the cars, they don't really see it. We see it, the attitude of his car is a little bit more I guess 'yawed out' more than everyone else's.
"There are reasons for that. We as a team are starting to pinpoint that and really starting to show up."
Many teams are using the two-day test at LMS to experiment with setups similar to what they believe Edwards has.
NASCAR allows only a quarter-inch adjustment in the rear housing and monitors it with gauges. Tony Eury Jr., the crew chief for Dale Earnhardt Jr., can't go quite that far without making the car tough for his driver to handle.
"It's a driver feel, there's no doubt," Eury said. "Some drivers like it. Some drivers don't."
Edwards apparently does. He's used it to win at 1.5-mile tracks at Las Vegas and Texas and the 2-mile California Speedway. He was headed for a win at 1.5-mile Atlanta before his engine expired late.
"The car is just a little bit more sideways," Hamlin said. "Is [Edwards] able to run a bit looser than everyone else? Probably not. I know a lot of guys love loose race cars -- and I do myself.
"It's something they figured out and hats off to them because these are the tracks you really need to perform at and they are doing a really good job of it."
"That's a piece of it," he said of the yaw. "That's the biggest thing people can see, so everybody is like, 'He's turning the car sideways.' We're doing it to understand what's going on."
Mark Martin, who finished second at Richmond last weekend, applauded the efforts of his former employers at Roush Fenway Racing.
"[NASCAR] has regulated that area of making side force," he said. "They were the first to figure out how to get side force without bending the rules. I think the garage knows to some degree about all of that. The garage is playing with that."
Martin said some of the credit also has to go to Edwards because he is able to handle the car better than anybody else, in large part he said because of his dirt-track racing experience.
"We're always trying to figure out what the fastest cars are doing so we can add that to what we're doing," he said. "Carl's been fast at other than mile and a halves, too. Carl had a lot to do with that, too."
Edwards declined to comment on what's being done to the car to make him so strong on 1.5-mile tracks, saying only that the intermediate tracks give him the same feel he had on smaller half-mile dirt tracks in Missouri.
"I'm not going to say," Edwards said, being as coy as was he was at Texas when asked if he could have gone faster. "It's better if people think in their own mind what is going on."
But Edwards did say these tests are important if he plans to keep his advantage.
"That's what we have to," he said. "Anytime you have a test, everyone is going to learn, so you have to learn just as much, or you'll be behind."
David Newton covers NASCAR for ESPN.com. He can be reached at email@example.com.