SPARTA, Ky. -- NASCAR's latest round of rules changes takes effect for the first time at Kentucky Speedway with modifications to the side skirts and sway bar.

The aerodynamic change is specific for intermediate tracks, including Kentucky's 1.5-mile D-shaped oval. NASCAR increased the ground clearance for all side skirts by one half-inch.

"I think the intent of that change is to reduce the dependency on aero grip and hopefully, from a fan's perspective, produce better side-by-side racing because you don't depend on that grip so much to make your car perform."

--BRAD KESELOWSKI

NASCAR issued a technical bulletin to teams outlining the changes, right-side skirts now must have a minimum clearance of 4.5 inches, with a maximum clearance of 5 inches. Left-side skirts must have a minimum clearance of 5 inches with a maximum clearance of 5.5 inches.

"I think the intent of that change is to reduce the dependency on aero grip and hopefully, from a fan's perspective, produce better side-by-side racing because you don't depend on that grip so much to make your car perform," Brad Keselowski said. "So I think that's a great change and, to the best of my knowledge, has the unanimous support of the garage, so I'm happy to see that."

Jimmie Johnson is taking to the changes well. He won the pole for Saturday night's Quaker State 400 with a speed of 181.818 mph (29.700 seconds).

"The skirt changes will be a significant reduction in downforce to the cars. So we're looking forward to it. I think the more we do to make the cars difficult to drive, the more it comes my way," Johnson said.

Dale Earnhardt Jr. also thinks the changes will work in his favor.

"I think the changes to the side skirts are actually going kind of in my direction to help me," said Earnhardt, who qualified in seventh position (180.222 mph/29.963 seconds). "I like the cars to be sliding around, slick, and up on top of the track and difficult to drive. It's taking a little of the comfort out."

Carl Edwards isn't so sure Kentucky is the right place to judge the changes, given the track's bumpy nature. But he appreciates what NASCAR is trying to achieve.

"I think NASCAR is going in the right direction trying to get the cars so we can pass, race closer and, even though this car will be gone soon, I think any of those changes that take aerodynamic forces away from this type of racing will be good for NASCAR," Edwards said. "They can [take] the rear spoilers off them, cut the splitters off the front, raise the car 3 inches and I am happy. The less downforce we have the better."

In an effort to maintain consistency in rear sway-bar setups, both the right- and left-side rear sway bar arm connecting the links must be perpendicular to the ground from all viewing angles when car is at ride height.

This change may have a greater impact on some teams which may have found an unfair advantage, although certainly within the rules, by using the sway bar and the trailing arm to help the car have more skew.

"I think as you looked at the cars that had been doing that I think they had been doing it for several weeks and found a lot of speed with that," Kevin Harvick said. "We had a lot of speed and were trying to catch up and had spent some time in developing parts and pieces to get to that. It was just going to keep evolving from there. I think NASCAR just decided to stop it before it got out of hand.

"There is a lot of force and pulling and pushing with that particular method of the way things were used. You had a potential to break some parts and pieces. That is what this sport is about though, being innovative, and kudos to those guys for figuring it out. The guy who figures out the next thing that NASCAR makes a rule about and wins a few races from it is what this sport is built on."