In the name of selling NASCAR tickets, Lowe's Motor Speedway President H.A. "Humpy" Wheeler has poked his head inside a tiger's mouth during a prerace stunt; hired a daredevil to jump a school bus over a 213-feet ravine filled with junked cars as flames erupted; and staged a reenactment of the 1983 U.S invasion of Grenada, complete with soldiers rappelling from helicopters onto the infield and firing howitzers loaded with blanks at front-stretch luxury boxes.

But in tinkering with the surface of his 1.5-mile superspeedway to create more action-packed racing, some NASCAR drivers fear stock-car racing's ultimate promoter may have gone too far.

The proof will come in Saturday's UAW-GM 500. Based on qualifying, it may be the fastest 500-mile race ever run on the storied oval just north of Charlotte, where Elliott Sadler won the pole Thursday with a record lap of 193.216 mph. On the other hand, it may set a record for crashes, with speeds eclipsing the limit of drivers' skill and tires' durability.

"There's a difference of opinion down there in the garage," Wheeler conceded, "and that's okay. When you've got that, you know you've challenged them. Most people don't like to challenge drivers, but I do. I don't want to take it over the edge; I just think you've got to get it close to the edge to make it work."

Saturday's 500-miler is the first major NASCAR race held at the track since Wheeler tried to remedy problems caused by grinding down bumpy patches in the racetrack's asphalt on the eve of the Coca-Cola 600 in May. The goal was to generate more side-by-side racing and passing. In that sense, the grinding worked. The May race produced 37 lead changes, with nearly half the field (21 of 43 drivers) leading a lap. It also produced a thrilling finish, with Jimmie Johnson edging Bobby Labonte for the victory by 0.027 of a second -- a margin so razor-thin it was barely perceptible to the human eye.

But the race was a crash-fest from green flag to checkered, with wrecks bringing out a record 22 cautions. There were so many spinouts and crashes as drivers careened around the asphalt, which had been ground in certain sections only in an effort to orchestrate more passing in Turn 2, that more than one-fourth of the race (103 of 400 laps) was run under the yellow caution flag. The repeated delays, as track-workers cleared debris and mopped up oil, dragged the race out to 5 hours 13 minutes.

"That was not good," Wheeler acknowledged. "Then again, nobody left!"

NASCAR tracks have distinct personalities, with quirks and challenges that demand different skills. The best drivers learn to master each track's quirks, much like great golfers master the nuances of different courses. By extension, a track owner can manipulate the way his track races by repaving its surface, applying an asphalt sealer or grinding bumpy sections, much like a golf-course operator can lengthen the rough, narrow the fairways or leave the greens unwatered.

While most NASCAR drivers felt Wheeler's intentions were good in selectively grinding Lowe's racing surface last spring, many blasted the result and complained that he had ruined one of the sport's best tracks.

"They looked at the racetrack and said, 'How can I manipulate this to make it more exciting?' " said Mark Martin, a four-time winner at the track. "That's what we dealt with in May, which was, in my opinion, not the right thing to do."

Wheeler responded by regrinding the oval in a more consistent fashion, so there wasn't a jarring transition between rough patches and smooth. It did little to allay drivers' concerns, however, after six cars crashed in two days of testing in September, with two of NASCAR's most accomplished racers -- Tony Stewart and Greg Biffle -- wadding up two cars apiece. So Wheeler hauled in a contraption that drags 12 used racing tires behind it, and ran it over the track's surface to coat the asphalt with rubber in hopes of helping the racecars grip the track better.

This week's qualifying and practice sessions proved the method successful, but all the extra grip has made the cars go even faster and triggered a new round of worries.

"As fast as we're going these days, especially because of the aerodynamics, we're all concerned about abusing tires," four-time champion Jeff Gordon said. "It's so fast that you're afraid of what you're going to do to the tires."

Said Stewart: "If you hit the wall this week, it's going to hurt, for sure. It's going to leave a mark."

To Wheeler, the controversy over the record speeds and uncertain surface is reason to celebrate rather than fret.

"To me it is the essence of an event: to create tension!" Wheeler said. "Great events always have tension. You don't want people going to a track that's boring and dull, and nothing happens in the prerace, and somebody says the prayer and 'Gentlemen start your engines,' and all the sudden you're yawning. We're selling excitement! You also don't want to take it over the line. When you're at the edge of the cliff, you've got to be careful. I think I've been around long enough that I know where that edge is, but there are people who think I don't. And some of them are good friends of mine."

Martin is an example. "You're talking to an old-timer here," said Martin, 46. "I say if the race is too boring, stay home. That's not what Humpy would say. I don't own this racetrack; I'm not the one trying to fill the seats."