Tony Stewart
Credit: John Harrelson / Getty Images

On a steamy Monday afternoon at Eldora Speedway, the dirt track that Tony Stewart owns in rural Ohio, the two-time NASCAR champion sits in a ratty pickup, traveling a less-than-epic 35 mph. He leans his elbow out the open driver's side window. Big clumps of mud whip toward the windshield like gunky shrapnel. The wipers flick, to little effect. Stewart moves his head around, trying to see through the clay tapestry.

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"As much as I'd love to listen to the radio right now," he says, "I'm listening to the dirt." You listen to dirt?

"Yeah," he says. "I can tell going through it how wet it is, if it's packing in nice. You just hear the moisture squishing. When it's got a lot of water in it, it makes a really sloppy sound. Hear that flapping noise? Then all of a sudden it got real squishy-sounding? That's a lot of water in there."

Do you always listen to the track when you race?

The way he looks at me, I realize I've asked a stupid question.

"Nah," he says. "You don't have to listen to pavement. It's all pretty much the same."

In the past three hours, Stewart has driven a neon-green Arctic Cat ATV, a tractor pulling two enormous "sheep's foot" rollers, a massive water tanker, and a broken-down old Chevy pickup, which he pummeled until the left front tire blew out and he replaced it with his current, nearly identical ride – all in an effort to flatten this track into the perfect driving surface. The former NASCAR champ is about to host a charity race here, featuring more than 20 of NASCAR's leading drivers. In terms of glamour, Eldora's dirt-caked rim walls and clumpy grass are a faint whisper of the 150,000-seat courses these guys are used to, but this track belongs to Stewart, and he wants to make damn sure his friends can drive on solid clay.

In the infield, a good-looking track employee waves Stewart down. Stewart senses an opportunity to upgrade.

"I'm gonna take this girl around here for a sec," he says.

Want me to get out? I ask.

"Yeah," he says. "Otherwise your ears might start to bleed."

An hour and a half later, his dirt-track date complete, Stewart pulls back into the infield. He has at least a four-day growth of beard and a fast-food paunch and wears jeans, sneakers, sunglasses, a mesh cap, and a light brown T-shirt bearing a Miller High Life logo. He looks more like your cousin returning unshowered from a fishing weekend than the male models who populate the NASCAR circuit. (Later, when I ask him if he has a workout regimen, Stewart mumbles something about how he sometimes lifts heavy stuff around his property in Indiana.)

"Fuuuuuuck," he says. "I've got a lot of work to do. At least we had a couple of breaks. Last year, I was on that tractor for six hours straight. Make no mistake, you get tired of driving."

It's hard to imagine Stewart saying that. As he writes in his auto­biography, "I was drawn to anything with wheels from the day I was born." He grew up in Columbus, Indiana, the guts of Indy 500–worship country, and started racing go-karts when he was seven. As a pro, he competed in both open-wheel and Indy car circuits before switching to stock cars in 1999 and hitting it big-time. (His crowning glory that year: an epic 1,100-mile sprint in which he raced in the Indy 500 and the Coca-Cola 600 in Charlotte, North Carolina, on the same day, finishing in the top 10 in both.) Even after winning two NASCAR championships, he flouted his contract with Joe Gibbs Racing and kept racing midget cars on small-town tracks under a fake name. Next season, he'll be leaving that racing team and starting his own, which means he can drive anything he wants, whenever he wants.

"In my lifetime," Stewart's hero A.J. Foyt once said, "there's probably been only two or three guys I've known who could drive just about anything they sat down in, and Tony Stewart is one of them."

In the infield, Steve, one of Stewart's seemingly endless staff of loyal employees, approaches with a paper bag.

"I got a cheeseburger, soda, and chips for you, Smoke," he says. Smoke is Stewart's nickname. People started calling him that in 1991, when, as a USAC rookie, he had a habit of slipping his right front tire. The name stuck once he started blowing engines in NASCAR races.

Stewart rips open the wrapper and starts wolfing down the burger as though he hasn't eaten for days. "In this line of work," he says between bulging mouthfuls, "you learn to eat when you can." Almost before he has a chance to swallow, Stewart is up in the cab of the tractor, dragging the sheep's foot rollers behind him.

"Smoke's always driving something," Steve says.