'Productive' test gives NASCAR lots to evaluate
October 17, 2013, Kenny Bruce, NASCAR.com
NASCAR officials are still evaluating results and dissecting data gathered from Monday's test at Charlotte Motor Speedway, a daylong effort that Robin Pemberton, NASCAR vice president of competition, described as "a good productive test."
Two teams from each of the three manufacturers -- Chevrolet, Ford and Toyota -- participated as officials attempted to hone in on a 2014 rules package for intermediate tracks.
"A lot of times, it's as important when you test just to get some of the items off the board," Pemberton said. "In our situation, it's OK to do things and say 'OK, get that off the slate, it's a non-keeper' or 'it's a keeper.' "
Pemberton said changes such as different ride and spoiler heights had been tested previously and showed promise. Monday's test was part validation of those findings as well as an opportunity to gather additional information with a variety of other packages.
"There are some things that we did to the car for 2013 because we needed the travel; we had certain shapes of splitters and things like that because the car went through four inches of travel," he said. "We addressed a few of those things. … We had a person assigned to each car that debriefed the driver when he got done with all of his runs. As you can imagine, that's a lot of information to melt down."
Multiple tests in 2012 as the series prepared to roll out the Generation-6 car this season had shown that lessening the amount of downforce on the cars was not conducive to providing close competition on the track, as many had believed.
"We went down a path of testing cars in traffic; we knew it was important to run with multiple cars on the track with different configurations of aerodynamics, splitter sizes and shapes, pans underneath the cars, smaller spoilers, bigger spoilers, a whole list of things," he said. "One of the things toward the end of the summer … we were at the all-time low for downforce (numbers) … when we looked at all the things we had done, it became apparent that the more downforce we took away the farther apart the cars got in traffic, the more disturbed they became."
Driver feedback on Monday, he said, mirrored what officials had already come to understand.
Finding ways to lessen the aerodynamic impact of the lead car on a trailing car remains the focus for the intermediate tracks. And while gains can be made through the use of computational fluid dynamics (CFD) and wind tunnel testing, results can vary when multiple cars are involved.
"When teams go to the wind tunnel and work on their car, they work on their car to create the most downforce, the least amount of drag and all this other stuff," Pemberton said. "When we're developing a rules package, as of late, what we work on is getting the car that's No. 2 in line the best that it can be.
"Sometimes some of the things that you do are counter-intuitive for a single car but they're better for a multicar situation. That's what we work on. It's difficult, it's expensive, the runs are long, and it takes a lot of time to get that done. There are no wind tunnels that can run two, three, four or five cars (simultaneously).
"We're fairly comfortable with a two-car CFD but … even the scale model tunnels, it's very difficult to run two (cars) in those."
Eventually, what has been learned must be verified on the track. "And it doesn't always work," he said.
"There are things we saw Monday that gave a little different result than what we saw in some of the CFD studies."
No additional on-track tests concerning the 2014 rules package are currently on the schedule, but Pemberton didn't dismiss the possibility.
"We're going over the information," he said. "The results of some of the things we got on Monday may be enough to add to the package next year. Right now there's nothing on the books."