NASCAR research and development usually focuses on minute technical details such as gear ratios and air displacement. Last winter, one topic was fan displacement.

The racing giant took note of increasing numbers of empty seats and declining television ratings during the 2006 and '07 Cup seasons. It determined its most ardent supporters were watching six fewer minutes of the races. Research also showed those fans were attending half as many races as they used to – an average of three to five as opposed to six to 10.

NASCAR has addressed what it considers erosion to its foundation, the core fans who have followed the sport for years – long before there was a Chase, a Texas Motor Speedway, a Car of Tomorrow or a Toyota parked in Victory Lane.

That doesn't mean going back to abandoned tracks such as Rockingham or North Wilkesboro. But NASCAR chairman Brian France and several NASCAR executives talked with track presidents to get an idea of how to better serve the loyal fans.

The sanctioning body has a new marketing campaign, "Our NASCAR," designed to thank fans, especially the longtime fans, and remind them why the sport means so much to them.

It also has loosened rules pertaining to driver conduct and has done an about-face with tangential issues such as race day entertainment.

"NASCAR is different from other sports in that most people don't grow up competing in it like baseball or football," said Mike Helton, NASCAR's president. "So NASCAR fans must spend more time to understand the nuances and strategy of the sport.

"That commitment and understanding translates into fans with deep roots in the sport – they're the so-called 'core fans.' We have a tremendous respect for these most dedicated fans who represent such a big part of 'NASCAR Nation.' "

So far this season, the news is getting a little better for NASCAR. Television ratings for the first five races on Fox showed a 7 percent increase over 2007, not counting California's Monday finish. (It's still up 4 percent if you include California.) Ratings for viewers 50 and older are up 14 percent. Overall ratings in the Dallas-Fort Worth market have increased 13 percent.

Attendance at the Daytona 500 increased slightly, but it lagged at Las Vegas, Martinsville and Atlanta. Inclement weather might have hurt the Martinsville and Atlanta races. TMS officials expect about the same number of fans for today's race as last year.

It might be an indicator that the core fans are re-engaging with a sport. Or at least they are watching more of NASCAR's most popular driver, Dale Earnhardt Jr., as he stays in contention most weeks with a top team.

"There's no doubt that everyone agrees there was too much change in a very short amount of time," said Ray Evernham, a longtime participant in Cup racing. "I think what NASCAR is doing are good steps."

Andy Hillenburg talks to some of NASCAR's core fans every day. That's part of the responsibility that comes from purchasing North Carolina Speedway in Rockingham for $4.4 million in an auction in October.

Longtime NASCAR fans grew up around the track, which held Cup races from 1965 until 2004. It was sold to Speedway Motorsports Inc. and its last remaining Cup date transferred to Texas Motor Speedway.

Hillenburg's e-mail inbox fills up and his phone rings regularly as passionate fans want to talk about coping with widespread changes to the sport in recent years. Many of them feel NASCAR forgot about them in an effort to attract new fans.

Some are disheartened by NASCAR's departure from traditional locations such as Rockingham and North Wilkesboro. Others don't know what to make of a playoff system, a foreign manufacturer and a new racecar.

"What's happened more than anything is that there have been changes," Hillenburg said. "Anytime you change something someone really likes, they say, 'Why did you do that?' Fans were frustrated. They didn't like all the change."

Core fans are vocal. Many wrote letters in the off-season to NASCAR headquarters, mostly addressed to France. One fan detailed 12 things wrong with the sport. Another writer, Chris Hohman from Washington, signed his letter as an ex-racer and "diehard fan and I want to stay that way."

"I know they won't go back to the way things were," said Hohman, 45. "I can understand bringing in more fans, but I feel like it's pushing me away. It's not the way racing used to be."

NASCAR also talked with its television partners about moving some races earlier in the day.

"The old line, hardcore fans were accustomed to going to church on Sunday morning and watching it that afternoon," NASCAR spokesman Jim Hunter said. "We can't start races all the time like that anymore, but we're trying to come up with more consistent start times."

Even the pre-race entertainment was analyzed. NASCAR tried to attract new fans by partnering with former American Idol winner Kelly Clarkson, for instance. Hunter said many longtime fans didn't like it and wanted the sport affiliated with country music again. This season, fans will see Garth Brooks and Brooks & Dunn in some NASCAR ads and at big races.

The core fan was also in mind when NASCAR decided to get away from penalizing drivers from speaking their minds.

"When it comes to breaking the rules, we're not going to be soft," Hunter said. "But when it comes to taking the personalities out of the sport, we're going to let boys be boys as long as we can somewhat keep it under control."

Fans would like ticket prices to be kept under control. TMS president Eddie Gossage said the track doesn't ever increase tickets prices across the board. He said there is a slight price increase for some of the higher-priced sections this season, but the lower-priced seats remain the same.

As part of a TMS promotion with 7-Eleven convenience stores, fans can purchase four backstretch tickets, plus food items for $159. Twice as many of the packages have been sold over those from last year, which Gossage said is a sign fans are becoming more price-conscious.

Gossage said he is encouraged by the ratings and the attendance at some of the early-season stops.

"I will give NASCAR some credit because the first thing you've got to do is say, 'Guys, we're doing something that isn't quite working,' " Gossage said. "Then you have to figure out what to do. It's up to the core fan to support the sport, and I think they're doing that right now. It's a good sign so far."