SONOMA, Calif. -- Another time and Tony Stewart's 29-race winless streak would devastate the driver, his anger coiled ready to spring.

Not now. Stewart admits he's frustrated about his drought because he's come close to winning, including last week's runner-up finish at Michigan. He also knows one driver can't break the stranglehold Roush Racing and Hendrick Motorsports have on NASCAR Nextel Cup racing.

"There's something in the equation that they've figured that's working out for them and it's out job to ... do the same thing,'' said Stewart, who starts seventh in today's race at Infineon Raceway.

As the Roush and Hendrick teams dominate -- they've won 18 of the last 21 Cup races -- they're also changing the sport. Their success forces other teams to make major changes or fall further behind.

Among the moves some teams have made:

n Chip Ganassi Racing has dedicated people to improving its aerodynamics and gave Casey Mears a fast car at Michigan. A newer version should be ready in two weeks at Chicago.

n Evernham Motorsports will add a third team next season to join Kasey Kahne and Jeremy Mayfield.

n Robert Yates Racing plans to test at every track that has a Cup race between now and Richmond in September with Elliott Sadler and Dale Jarrett.

n Richard Childress Racing has hired additional personnel.

n Nearly every team has added a driver development program after seeing how both Roush and Hendrick groomed young drivers, including defending series champion Kurt Busch, Carl Edwards and Kyle Busch.

Forget the Chase for the Championship. This is all about the chase to catch up.

"At the start of the season, it seemed like the Roush cars and the Hendrick cars were way out there and had a bigger gap than normal,'' said Andy Graves, team manager at Chip Ganassi Racing. "It's been quite a while, to be honest, that I've seen that big of gap between the cars that run in the front versus the next group of cars.

"Lately, it seems that Roush has maintained their pace and Hendrick has slipped back between Roush and where the next group of us are.''

Roush cars have won six of the last nine races. Car owner Jack Roush saw his cars take four of the top five spots at Michigan last weekend.

Hendrick has slipped as Jeff Gordon has tumbled in the standings, but Jimmie Johnson remains the points leader. Also, Kyle Busch is one of the sport's hottest drivers with four top-10 finishes in the last five races.

Roush and Hendrick also took the first three starting spots for today's race. Gordon starts on the pole with Johnson beside him. Mark Martin starts third, best among the Roush cars.

That's about how it has been the last two months. The only team to win a Cup race other than Roush or Hendrick during that time is Evernham Motorsports with Kahne at Richmond.

Evernham admits two-car teams are nearly extinct. He'll add a third fulltime team next year and said that's to keep up with Roush (five cars) and Hendrick (four cars). More cars mean more personnel and more information. If a larger group is organized and communicates well, the extra information is nearly too much for smaller teams to beat.

"Right now, I'm one of the only two-car teams,'' Evernham said. "The handwriting is on the wall.''

Car owner Richard Childress also sees it, but in a different way. His three-car team has struggled, although Kevin Harvick's win at Bristol is one of the few non-Roush and non-Hendrick wins since October.

"It's hard when you get beat,'' Childress said. "The one [team] I look at harder than Roush is Hendrick because they've got a Chevrolet. A Chevrolet outruns us, we've got a problem. We've got the same stuff as they do.''

Childress has hired another engineer and hired a research and development director for the engine shop to try to close the gap.

Ganassi's team focused on engines last year. Now, they're studying aerodynamics. Graves said they're spending twice as much time in the wind tunnel. He also said that the team has about 20 people spending most of their time on that issue. The car they gave Mears last week was better. Mears qualified second and ran among the leaders early until slow pit stops dropped him deep in the pack and he finished 21st.

Stuck in the pack is how many teams feel when compared to Roush and Hendrick. And no team has shown any signs of challenging either team eight months after their streak started.