Hampton, GA (SportsNetwork.com) - Sunday's 500-mile race at Atlanta Motor Speedway will feature the new 2015 rules package in the Sprint Cup Series for the first time.
Last weekend's Daytona 500 featured the 2014 rules package. It will also be used for the spring and fall races at Talladega as well as the July event at Daytona.
NASCCAR made significant rule changes for the Sprint Cup cars this season, including lower horsepower and modifications to the cars' aerodynamic package. The horsepower was reduced from 850 to 725 through a tapered spacer, which is an engine part used in the Xfinity and Camping World Truck Series. Revisions to the aero package include: rear spoiler adjustments to 6 inches high (2014 height: 8 inches) and minimum vehicle weight drops 50 lbs. via ballast reduction (2014 weight: 3,300 lbs. without driver).
Other rule changes for this year are: roller valve lifters to replace flat valve lifter, lower rear differential gear ratios targeting 9,000 RPM, an optional driver adjustable track bar and a 38-inch wider radiator pan.
Thursday's open test session at Atlanta allowed Sprint Cup teams to familiarize themselves with the rules package for the first time. Reviews were mostly favorable.
Some drivers did not notice any significant difference with the handling and speed of their cars.
"I really didn't notice anything," said Kyle Larson, the driver of the No. 42 Chevrolet for Chip Ganassi Racing. "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 we have less downforce too. It still feels fast. Maybe once we get to Michigan or a track where we will probably run even more wide open the we'll notice more. I really didn't notice much difference between this year versus last year."
Larson led the way in Friday's Sprint Cup practice at this 1.5-mile racetrack with a lap at 192.989 mph. Kevin Harvick, the defending series champion, was second quickest at 192.607 mph, followed by David Ragan at 192.547 mph. Ragan is driving the No. 18 Joe Gibbs Racing Toyota in place of the injured Kyle Busch. Joey Logano, the Daytona 500 champion, was fourth fastest (192.373 mph).
Drivers and teams are eager to find out how the cars perform in race conditions. Prior to Thursday, no teams had time on the track to test the new rules package since NASCAR now has a ban on private testing.
"My (car) drove pretty good and had a lot of grip," Greg Biffle, the driver of the No. 16 Roush Fenway Racing Ford, said after Thursday's test. "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...My car didn't feel hugely different. I could tell it's got less power, but it wasn't like, 'Oh my gosh, this is a whole different car'."
Carl Edwards, in his first season driving the No. 19 Toyota for Joe Gibbs Racing after spending the past 11 years with Roush Fenway, noticed a few slight differences with the car during the open test.
"The car feels great," Edwards said. "I'm still getting used to the seat and the wheel in the right position and getting my steering box the right speed and all that stuff, but it feels good.
"The new package is a little bit different. It feels like we have more on throttle time. We're not out of the throttle as much, so I have to get used to that a little here. It changes the way you drive this place being on the throttle a little more."
Edwards' first career victories in both Sprint Cup and Xfinity occurred at Atlanta in March 2005.
Forty-seven teams are on the entry list for the Folds of Honor QuikTrip 500.
Series: NASCAR Sprint Cup. Date: Sunday, March 1. Race: Folds of Honor QuikTrip 500. Site: Atlanta Motor Speedway. Track: 1.54-mile oval. Start time: 1 p.m. ET. Laps: 325. Miles: 500.5. 2014 Winner: Kasey Kahne Television: FOX. Radio: Performance Racing Network (PRN)/SIRIUS NASCAR Radio.