Teams learn new package in Atlanta open test

The open test gave teams an opportunity to learn how their cars react with a rules package that includes less horsepower and downforce. It also provided them with additional track time leading into this weekend's Folds of Honor QuikTrip 500 (Sunday, 1 p.m. ET, FOX) at AMS.

"I felt like I needed a little bit more front turn, but as the session went, it seemed like we didn't really slow down and everybody else did, which was a good thing," Roush Fenway Racing driver Greg Biffle said after the first session, which lasted an hour and 45 minutes.

Biffle said he hoped to pick up speed in the second session "and then hold consistent," and that was indeed the case although overall, the speeds were slower in the second stint.

McMurray's lap of 191.549 mph was tops in the opening session; Gordon's 188.424 paced the final segment that went five minutes short of two hours. Biffle improved his speed from 185.536 mph to 186.975 mph.

"My car didn't feel hugely different," Biffle said. "I could tell it's got less power, but it wasn't like 'Oh my gosh, this is a whole different car.' "

Gene Stefanyshyn -- NASCAR Senior Vice President, Innovation and Racing Development -- said that while officials took note of the information gleaned from Thursday's practice, the track time for the teams and data they gathered was more crucial.

"We collected all our data and used that to put together a package ... in collaboration with our teams, drivers, etc.," he said.

"Today the amount of data we're collecting is very limited; the teams are collecting a lot of data. ... But as we get into our races, we will be collecting, harvesting the data off of the race, and that's really where we know what's going on. In practice, you don't have the same situation as in a race environment."

Likewise, Stefanyshyn said, a four-hour session is too little from which to draw conclusions that could have major implications.

"Realistically, you probably need five or six races of data points under your belt to draw any significant conclusions," he said.

Coors Light Pole Qualifying for Sunday's race is scheduled for Friday at 5:45 p.m. ET (FOX Sports 1).

No tests are scheduled for nine of the 23 tracks hosting Sprint Cup events in 2015.

Here's a complete look at the 2015 testing schedule:

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