PHILADELPHIA — The news that General Motors plans to trim 30,000 workers and close nine plants left some people in NASCAR unsettled. They wondered if GM's business problems would affect the company's commitment to NASCAR.

"I get asked that quite often," Mark Kent, GM's director of racing, said Wednesday from his Detroit office. "What I tell everybody is, although racing is a sport, companies engage in motor sports for business reasons. At GM, all our racing programs give us tremendous marketing value. It's a very cost-effective way to put our products and brands in front of automotive enthusiasts."

To clear up any doubt, Kent said, "We're committed to racing."

Chevy almost has to be in NASCAR. If GM withdrew its Chevy brand, its absence would give Ford and Dodge a huge marketing advantage.

According to Kent, more than 40 percent of NASCAR fans own GM products. "Of NASCAR's 75 million fans, 13 million attend races," he said. "At many of these races, we are able to display our whole lineup of Chevrolet products. NASCAR fans buy new cars at a higher rate than the national average."

Chevrolet is off to an excellent start in the Nextel Cup series this season. Led by Jimmie Johnson, six of the top 10 racers in the series drive Chevrolet Monte Carlos.

Kent declined to disclose GM's financial investment in NASCAR. He said the company provides "some funding in the way of technical support."

Tech support in racing generally leads to improvement in the production of cars for all manufacturers.

Everyone at GM, Dodge and Ford is aware that the investment in NASCAR probably will have to be substantially increased with Toyota's entry in the Cup series next year. Toyota brings deep pockets to any racing series it competes in. "(Toyota's presence) will likely raise the cost of competing," Kent said. "(But) we raced against them in the Craftsman Truck Series and we compete against them in the showroom. We welcome competition. We see Toyota as a new challenge in 2007."

Earnhardt energized

A rejuvenated Dale Earnhardt Jr. (sixth in points) can look back on missing last year's Chase for the Championship without punching the nearest wall. As disappointed as Earnhardt was, when he realized he wouldn't be part of the Chase (19th-place finish), he relaxed.

"It was kind of nice to take a break from the spotlight a little bit, kind of recharge your batteries," he said Wednesday during a break from testing at Richmond International Raceway. "We were frustrated when we didn't get the finishes. There were 10 or 12 races where we should have finished well, and either I made a mistake, or we had a mechanical failure."

Earnhardt is enthusiastic about his team. "I just am really lucky to be driving the car that they put together," he said. "They build a great race car."

Biffle-Busch battle

Greg Biffle, expected to be a contender for the Chase title, is off to a terrible start.

The winner of a series-high six races last year, Biffle is 23rd in points.

He led 49 of the first 82 laps last Sunday at Texas before his Ford was hit from behind by former Roush Racing teammate Kurt Busch.

Biffle and Busch were not happy with each other. Busch said Biffle slowed in front of him.

Biffle said, "At some point, common sense has to set in and (you) say, 'I can't run into the back of a guy at a superspeedway going 175 mph.' All you have to do is lift on the gas pedal and elect not to run into the car in front of you. That's pretty unforgivable, I would say."

Following the accident that relegated Biffle to a 42nd-place finish, Biffle's girlfriend, Nicole Lunders, confronted Busch's fiancee, Eva Bryan.

NASCAR officials plan to chat with Lunders. Any more of this and NASCAR may institute a rule regarding behavior of girlfriends and fiancees.

Focus on Busch Race

With the Cup series taking its traditional Easter Sunday off, the Busch series race at Nashville on Saturday (4 p.m., FX) is the only NASCAR action this weekend.

Cup series veteran Kevin Harvick leads Cup rookie Denny Hamlin by 146 points in the Busch standings. Erin Crocker is doing double duty at Nashville on Saturday. She's in the Busch and ARCA races. The ARCA race will be televised at 1:30 p.m. on the Speed Channel.