CONCORD, N.C. -- Six NASCAR Sprint Cup teams went to Charlotte Motor Speedway on Monday to find out what works and what doesn't as the sanctioning body contemplates changes to the Sprint Cup car for 2014.
"Our objective here is to begin to shake down some potential changes for the 2014 season," said Gene Stefanyshyn, NASCAR vice president of innovation and racing development.
"This should be viewed as kind of an annual event that we'll be doing on an ongoing basis, with an eye to improve our product on the track."
Stefanyshyn oversees the activities at NASCAR's research-and-development center in Concord. He explained that the Charlotte test was designed either to validate or discard changes to the Sprint Cup car's aerodynamic package that had been developed on a theoretical basis but had yet to prove their worth on the track.
"We actually put it on the track and try it on the track, because there are no wind tunnels in the world where you can put six cars in or 10 cars in, and in CFD (computational fluid dynamics), you're working with one or two cars," Stefanyshyn said. "So we really do need to put real-world testing into our solution set. That's basically what we're doing here today."
The test featured two drivers representing each manufacturer: Brad Keselowski and Trevor Bayne (Ford), Jeff Burton and Jamie McMurray (Chevrolet), and Denny Hamlin and Brett Moffitt (Toyota). Moffitt was substituting for Brian Vickers, who announced Monday that the discovery of a blood clot in his right leg-the recurrence of an issue that sidelined him for six months in 2010-would force him to sit out the rest of the NASCAR season.
Monday's assignment for the test participants? To go through a checklist of seven possible changes grouped into three different configurations. On the menu were the addition of a roof strip, changes to the rear spoiler, the splitter, the rear fascia and the ride height of the Sprint Cup cars, among others.
"Our objective is definitely to impact the aero package of our intermediate racing to improve passing," said Travis Geisler, director of competition at Penske Racing. "They worked with all the different teams and all the different OEMs and tried to come up with some good ideas on what may impact drivers' ability to overtake."
Typically, the lead car in clean air has a decided aerodynamic advantage over the trailing car in dirty air. Some of the measures tested Monday are designed to minimize the difference in the aero capabilities of the cars that arise from their position in the running order.
To Geisler, the addition of the roof strip across the top of the car could be a significant change.
"You kind of look back to the old speedway days, when we had that strip across," Geisler said. "I think Nationwide cars ran that for a long time, and Cup ran it for a little bit. That's coupled with the rear spoiler to keep the downforce equal on the cars. When you put that strip on, you hurt the rear downforce a good bit, so they've responded with a bigger spoiler to keep the cars at an even downforce level.
"That, I think, has the best shot of anything of minimizing the drag on the trail car. That's really what we're hoping to do there, is give us some straightaway speed, where it looks like a boost button. Another factor-you'll see the holes in the rear fascia, where they've got a pretty fair amount of area opened up.
"Whenever you see a car that loses that rear fascia, their performance really improves, and that's because the downforce improves a lot with the air being able to get out from underneath the car instead of stalling underneath it and creating lift. I think that's a good step in the right direction."
Geisler also is optimistic about the efficacy of a staggered splitter.
"They've got a stepped splitter, where the splitter has a raised section," Geisler said. "The splitter's really sensitive when it's close to the ground. You get a lot of gain as you get close to the ground. That's why everybody goes to be sealed up (an aerodynamic seal that's as close to the track as possible).
"Well, if you're able to get that splitter in a little bit less of a sensitive spot, maybe the lead car doesn't have such an advantage when he stays sealed, and the trail car loses his seal a little bit, because he's in dirty air, and the front end lifts a little bit. I think that's a pretty decent idea. How we implement it and race it every week is something we're all going to have to think about."
Based on the Charlotte test, NASCAR will analyze data from timing and scoring and from the teams' electronic fuel injection systems, along with impressions from drivers and crew chiefs. Changes that make sense will be part of the new 2014 package.
"Today, if all the stuff works, it could all make it in," Stefanyshyn said. "I don't think it's all going to work, but that's the way these complex engineering problems are."