NASCAR drivers find few differences in cars at Atlanta

HAMPTON, Ga. — After months of speculation about how NASCAR's new rules package would change how the Sprint Cup Series cars drove and raced, the drivers finally got their first chance to take their cars for a spin.

The result after a 3.5-hour test at Atlanta Motor Speedway?

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

Drivers consider Atlanta to be the start of the real season because the Daytona 500 is one of just four restrictor-plate races on the 36-event schedule. This year, though, there's something extra to watch for.

Sunday's Folds of Honor QuikTrip 500 will mark the first race where drivers will experience such changes as a rear spoiler shortened by two inches (to take away downforce), a reduction in engine horsepower (by approximately 115 hp via tapered spacer) and a track bar which can be adjusted inside the cockpit.

There was no testing during the offseason, save for a Goodyear tire test in January at Las Vegas Motor Speedway, so most drivers hadn't tested with the new rules until Thursday.

And despite a controversy last year about NASCAR trying to slow down the cars — a decision that wasn't met with much excitement from the drivers — the speeds weren't very far off from 2014.

For example: In the morning test session, Jamie McMurray had the fastest average lap speed — 191.549 mph — which was barely off the fastest practice speed from last August's race weekend (Carl Edwards at 192.855 mph). It was quite a bit colder on Thursday, which increases grip, but the speeds were still relatively similar.

"I felt like the car really didn't drive much different here than how it did with the old rules package," Kyle Larson said. "I thought it still came up to speed pretty well. Maybe it doesn't carry to the end of the straightaway as hard as what it did before, but it still feels fast."

Edwards said there was a small difference in that drivers stay on the gas longer, which "changes the way you drive this place," he said.

"Even when you take away a little bit of power, we're making so much speed in the middle of the corner, it's really fast there," he said. "I think NASCAR is heading in the right direction by cutting the spoilers down. I think the farther we go in that direction, the better it's going to get."

Gene Stefanyshyn, NASCAR's senior vice president of innovation and racing development, said speeds were slightly above where NASCAR expected but it was likely due to the cold temperatures.

All of the changes, he said, are in an attempt to improve the quality of the on-track product.

"What we're looking for is lead changes, a lot of passing, close competition, good solid driving and an enjoyable experience for our fans," he said.

Another new rule the drivers are just getting to know is the adjustable track bar, which affects the handling when it is raised or lowered. Previously, a crew member had to adjust the track bar during a pit stop – but now drivers can just flip a switch while racing.

Teams have several different choices of where to mount the track bar switch, including on the steering wheel (as Edwards' team did) and on the seat mount by the driver's leg (as the Chip Ganassi Racing cars did).

So will drivers being able to make their own adjustments become a factor during the races?

"To be honest with you, I think that's going to be an opportunity for us drivers to screw ourselves up more than it is going to help us," Edwards said. "I ended up playing with it for a few laps and then put it right back where it was, because it wasn't doing exactly what I wanted it to do."

But Larson said a track bar adjustment he made helped during his exit from the corners.

"I think that will be a really neat tool that we get to use as driver," he said. "It is nice that they allow us to put a little bit more into the driver's hands."

Follow Gluck on Twitter @jeff_gluck

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