Kyle Busch and Kurt Busch are not twins.

There are differences between the sons of Tom Busch, who raised his boys in Las Vegas where they’ll race in Sunday’s UAW-DaimlerChrysler 400.

But, beginning with the strong family resemblance, there’s a lot more about them that’s the same.

Both, of course, have demonstrated their talents at an early age in NASCAR’s Nextel Cup Series.

When Kyle won the first of his two Cup races in 2005 on Sept. 4 at California Speedway, he became the youngest driver to win a Nextel Cup race.

He was 20 years, 4 months and 2 days old – four days younger than Donald Thomas when he won a race in 1952.

Kurt now has 14 career victories. Seven of them came before his 25th birthday, the same number the legendary Richard Petty won by that age. Only Jeff Gordon, who had 15 wins before turning 35, had more.

Kurt Busch, left, congratulates brother Kyle for winning the pole position for the 2005 Auto Club 500 at California Speedway.

But it’s not only success that the Busch brothers share. Controversy seems to follow them both, too.

Already this season, Kyle Busch has felt singled out for criticism about his driving style in the season’s opening events at Daytona. Then, last weekend in a Busch Series race in Mexico City, he drew the ire of fans there for an incident with Michel Jourdain.

“There have been some instances where I’ve put my car in situations where maybe I should have thought a little bit differently about,” Kyle Busch said. “But that’s any driver. … It’s all about trying to gain respect, that’s something that’s important to me. I hope I’ve done a great enough job on that. I’m only in the start of my second year, so there’s still a little bit more to do.”

Kurt, the older brother by nearly seven years, has his own situation to deal with. Roush Racing suspended him for the final two races of 2005 for an incident near Phoenix International Raceway in which he got a traffic citation. Kurt agreed to do community service as a result of that incident, but also finds himself dealing with the public relations backlash of that now that he’s in his new ride, the No. 2 Dodges owned by Penske Racing South.

Kyle Busch in the No. 5 car races brother Kurt during the Daytona 500 on Feb. 19 in Daytona Beach, Fla.

“I’ve tried so hard to try to fit in but I have kept kicking my own self in the shin,” Kurt said. “I’m just trying now to develop relationships.

“I was just here to race race cars. I came up through the ranks so fast that I never really developed relationships with people because I bounced from one series to the next. Now that I’m here (in the Nextel Cup series), I realize that this isn’t just about racing anymore. It’s about the relationships around you.”

The one relationship Kurt doesn’t have to worry about, though, is the one he has with Kyle.

“Kurt and I have a tremendous amount of respect for each other,” Kyle Busch said. “But there is always a sibling rivalry there, of course. The younger brother always wants to go out and outdo the older brother, so I’ve had that on me for a long time.

“Kurt kind of paved the way for me to get up here and knocked down a bunch of trees for me. Now that I am (racing in the Nextel Cup), I have to be able to make sure that I can do the job at hand as well as anybody else can.”

In November 2005, as Kurt sat out, Kyle won at Phoenix International Raceway and in victory lane dedicated his performance to his brother and his family’s name. Later, he walked out of a postrace media session when questions about the incident that led to Kurt’s suspension ticked him off, although he later returned to complete the interview.

With wins at Phoenix and California, nothing would please Kyle Busch more than to complete a sweep of the West Coast ovals by winning on his hometown track this weekend.

“It means a lot to us that Kurt and myself came from basically nowhere,” he says. “Nobody has ever heard of a race car driver who was born or grew up in Las Vegas. It’s a little different story from the older NASCAR days were, where everybody was on the East Coast. I think it’s cool.”

One of the pictures that Kurt has kept from his adolescence shows him and his hobby stock car sitting in a gravel parking lot outside a short track on the grounds of what is now Las Vegas Motor Speedway.

Behind him, you can see the construction cranes and part of the shell of the 1.5-mile superspeedway’s grandstands going up.

“Las Vegas is a unique town to represent,” Busch says. “It has a different feel. Everybody knows about Vegas, but the tough part with it is that everybody is shipped in from different areas. Nobody’s ‘from’ Vegas. But I am.”