Tempers tend to heat up as the NASCAR season winds down. And this week was no different as contenders for the 2005 Nextel Cup championship pulled into Atlanta Motor Speedway with bad blood still simmering from last Sunday's showdown at Martinsville.

Points leader Tony Stewart is steamed at challenger Greg Biffle, whom he blasted as "an idiot" for racing him hard over the final laps at Martinsville even though Biffle, who was running one lap behind, had no shot at winning, unlike Stewart, who was battling for the victory. Stewart is also peeved at Jimmie Johnson's crew chief, Chad Knaus, for disparaging remarks uttered over the No. 48 team's radio frequency -- fighting words, Stewart said, aimed at psyching him out of what would be his second NASCAR title.

But even Stewart realizes that retribution only goes so far. When the goal is getting to the front in a 500-mile race, cooperation is often a smarter play than competition.

That's why fans can expect to see a good bit of give-and-take among drivers on the high banks of Atlanta Motor Speedway -- at least until the final laps of today's Bass Pro Shops MBNA 500.

Atlanta's 1.54-mile quad-oval is among the circuit's faster tracks. But unlike the similarly shaped Lowe's Motor Speedway, whose record speeds earlier this month were achieved by grinding its surface glassy smooth, Atlanta's asphalt is abrasive enough to chew up tires, which scrubs off speed over the course of a 40- or 50-lap run. Combined with Atlanta's wide, well-worn racing surface, that lends itself to lots of side-by-side racing and passing.

With passing fairly easy, drivers are apt to be more generous in the early going -- whether that means letting a fellow racer back on the lead lap or, if it's no disadvantage to his own cause, letting a fellow racer lead a lap to collect five bonus points. It's a stock-car racing courtesy, but it's hardly without self-interest.

"If you know there's somebody that would help you, then you're willing to help them," Jeff Burton explains. "At the end of the day, that's what it's all about. You won't see people helping people who won't help them."

NASCAR's 43-car fields are populated by all sorts of drivers: bullies and sportsmen, overachievers and pure racers, the patient and the impetuous. And each has his own philosophy about helping a competitor, particularly with four races remaining before the champion is crowned.

Matt Kenseth flat-out refused at Kansas City three weeks ago when he was asked to ease off and let teammate Kurt Busch lead a lap for the five bonus points. Kenseth said Busch would have to earn points on his own; the championship race was too tight for favors.

Was Kenseth right?

"I think he made the right decision to try to win the championship," veteran racer Ken Schrader said. "As far as keeping the whole teammate thing flowing along smoothly, maybe he wasn't right."

In three decades in NASCAR's top ranks, Schrader has been part of multi-car teams and single-car teams. His philosophy on helping fellow drivers has never varied. First priority, help a teammate. Next, help a buddy. If it's no trouble, help somebody who really needs it. But always with the expectation that the favor is returned. It's not just good manners, Schrader says; it makes good sense.

Imagine you're running 12th, and the 13th-place guy catches you and tries to pass, Schrader explains. You can either spend five or six laps racing like crazy to hold off the 13th-place guy or let him pass. If you battle him for five or six laps, both you and the 13th-place guy will go slower racing side-by-side than you would have if you had fallen in line one behind the other. In the meantime, the leader will have extended his margin. So the smart play is to let the 13th-place guy pass, not lose more time than necessary and know you've got a favor coming.

"It's hard for spectators to understand, but until the late stages of a race, you're only racing the leader," Schrader says. "Until it's time to start paying money, you're only racing the leader."

Still, fans hate to see drivers let each other pass without a fight. Burton learned as much after letting Mark Martin, his teammate at the time, get a lap back in a race years ago only to see Martin go on to win it.

"I had a lot of people that expressed displeasure with that -- a lot of fans mostly, and some teammates," Burton recalled. "Even people on my own team told me I shouldn't have done that. But you have to, as in life, make your own decisions. If you're working with somebody who will work with you, and they've earned your respect, why not? This is a self-serving sport, don't get me wrong. Don't think for a minute when people help each other they're not doing it because they don't think they'll get that help back."

Tony Stewart is angry at the crew chief of Jimmie Johnson, shown closely tailing Stewart last week, but cooperation could be key today.Teammates such as Tony Stewart, left, and Bobby Labonte will help each other in races, as long as the favor is returned.