Tweaking his stock car a few minutes before the first race of the night, Randy Embrey peered through a crowd of racers to one of his harshest competitors -- his father.

Soon, the two would be battling each other and 20 more drivers around a quarter-mile oval dirt track before a crowd of 1,500 fans at Boone Speedway. Set amid cornfields, shoulder high this time of year, the speedway has attracted people from all over Boone County. Many of the fans personally know many of the racers and the mechanics and probably a few of the guys selling tenderloins and beer, too.

"That's how it goes," said Embrey, 41, a mechanic who lives near Boone, where there are really not enough people to race someone you don't know. "I've beat him; he's beat me. . . . There's competition, but when it comes down to it, I still want to be friends with everybody."

It is a midwestern, friendly approach to competition. That is the way it is here in Iowa, where dirt-track racing has become one of this state's most popular sports, and everybody knows everybody.

It is a poor man's version of NASCAR: unpaved tracks, cars made from junked frames, wrecks pulled off the course by hulking green and yellow John Deere tractors.

And people really like it. In rural Iowa, more than 50 new tracks have sprung up in the past decade -- all but one is unpaved -- and that is far more than other midwestern states, said Brett Root, a vice president with the International Motor Contest Association in Iowa.

Each summer, thousands of rural Iowans crowd grandstands to watch their neighbors and friends speed around short, muddy tracks. As many as 200 cars can show up for each race. The air smells of gasoline, oil and cigarette smoke. Speeding cars -- almost always made from parts bought at a scrap yard -- slam together on the track and fly apart.

"Around here, this is the only thing we can do, the only sport that can involve a lot of people," said Larry Nefzger, 58, who owns a tiny NASCAR merchandise shop in West Union, Iowa. "Even though everybody knows someone who's racing, nobody knows who won the races after an hour of drinking. A lot of [the excitement about racing] is that the week's over from work, they want to see their friends, they like the loud noise, they like the speed."

"This is like a small NASCAR track where there's a lot of passing, a lot of bumping, a lot of action," Rob Moser, 58, said after watching a race in Mason City, Iowa, this month. "They do it because they love the speed. You watch it because you are looking for an accident. You don't want somebody to get hurt, but you want to see something spectacular happen."

Unfortunately, accidents do happen. On Aug. 14, Maynard Davis III, 36, from Runnells, Iowa, died in a crash at a track in Des Moines, minutes into the race's opening lap. It is not known what caused his car to collide with another.

No one organization records how many people are killed during races at these tracks, but some track officials say such incidents do not happen often, perhaps once every few years. Though helmets, seat belts and roll bars are required, race officials say drivers participate at their own risk.

This sort of racing is literally dirt cheap because racing on dirt is less costly than preparing cars for paved tracks. Because most racers do not have much money, many try to land local company sponsorships that give them $300 to $500 for the season. Still, it is not unusual to meet racers who work two or three jobs to afford car parts or new engines or to come up with money for fees to enter races.

The cars can cost $10,000 to $20,000, and winners take home only about $200 on average from each race. After all that expense, there is little left to chip in for developing and maintaining paved surfaces. So tracks are often built over cornfields.

"Most of [the racers] don't have two nickels to rub together," said Bill McCroskey, a track promoter at the Southern Iowa Speedway in Oskaloosa, about 60 miles southeast of Des Moines. "A lot of them are robbing their parents and grandparents just to get to the track."

This is the place where old family sedans, abandoned from the 1980s, or tiny, rusting Honda Civics are reborn. Racers gut the insides, taking out everything except the driver's seat, including the windshields, to make the cars light enough to speed through turns at 70 or 100 mph. The doors are welded or chained shut to meet regulations. Roll bars crowd the cabins.

Although pavement racecars tend to be lower to the ground -- the weight is focused near the front to help the car speed around corners on oval courses -- dirt cars are jacked up. Weight is shifted to the back to help them swing their rear ends when drivers slam on the breaks and skid around turns.

But no matter the design, the cars cannot overcome a dirt track's largest impediment: mud. A couple of inches of rain can easily turn a dirt track into a mud bog and cancel the races.

Accounting for rain dates, rural tracks run about 20 races a season from April to September. And many tracks race four nights a week. Some, including the I-35 Speedway in Mason City, Iowa, even race on Sunday nights -- church time for many who live here.

Before the races one night not long ago, a Mason City track official led the racers in prayer in hopes of escaping impending rain. Afterward, he announced news of that night's bikini contest. That, the official said, would go on rain or shine.

"This here is actually our religious movement," laughed Kevin Opheim, 45, a plumber from Mason City who raced here that night. "This is what we pray for every weekend. There's nothing like getting dirt in your beer and having these cars rolling right in front of you."

Jeremiah Hurst's car gets bumped by Duane Coulson's at a race in Farley, Iowa. In the past decade, more than 50 unpaved tracks have sprung up in rural Iowa.Driver Melissa Johnson prepares with her husband, Monty, at right, for a race at Boone Speedway in Boone, Iowa, where fans know many of the racers.