It's the ultimate test of a Nextel Cup engine, a fall race at Atlanta Motor Speedway that combines cool temperatures and high speeds with RPMs that are always in the red zone. For more than three hours, pistons hammer and parts are stressed to a level rarely seen during the rest of the year. Most survive to a teardown and a rebuild and to race another day. But some expire in a spectacular fashion, overcome by heat and pressure, and leave a trail of billowing white smoke in their wake.

For an engine builder, Atlanta is a 1.5-mile, 200-mph crucible. For an engine builder with the top two cars in the Chase for the Nextel Cup, that's only magnified. Such is life for Jeff Andrews, the director of engine development for Hendrick Motorsports, and the man tasked with making sure Jeff Gordon and Jimmie Johnson get through Atlanta without going up in smoke.

"In terms of the Chase, there's pressure on an engine guy when you're warming them up in the garage anymore," Andrews said. "It's that time of year and emotions are high. You've worked all season long to get to that point, and the last thing we want to do is let anyone on the team down -- driver, crew chief, or whoever it might be. There's a lot of pressure in general this time of year being in the position we're in with those two cars, and having three cars in the Chase."

Gordon leads Johnson by 53 points entering Sunday's Pep Boys Auto 500, the seventh of 10 events comprising NASCAR's playoff. Atlanta has had its say in the Chase before -- Kurt Busch was pulling away from the pack before he blew an engine there in 2004, a failure that tightened the field and forced the then-Roush Racing driver to eke out a championship by just eight points. Gordon and Johnson lead their next closest competitor, third-place Clint Bowyer, by a relatively wide margin. One of the few things that could change that is an engine failure by one, or both, of the Hendrick drivers Sunday.

But judging from the results of this season, that's unlikely to happen. Combined, the four Hendrick drivers have experienced just one engine failure this season, that by Casey Mears at Darlington, since attributed to the change to unleaded fuel. A Hendrick engine department shaken by the loss of founder Randy Dorton in the team's 2004 plane crash has been restructured, rebuilt, and is humming along at a level that would make its former boss proud.

"I just feel like the shop as a whole has just risen to another level," said Andrews, who oversees the Hendrick engine program along with Jim Wall, the organization's director of engine engineering.

"You can spend millions and millions and millions of dollars a year and have all this great equipment in the shop, but you have to have the people in the shop operating that equipment with care and an attention to the details. These engines have to be prepped and assembled by people. People use their hands and minds and are paying attention to what they're doing. I give our entire group credit for that this year. I'm so very, very proud of the level they're at right now."

Of course, the machines help. Before they're put to use on an event weekend, the engines produced at Hendrick have to survive two 800-mile simulated races on the dynamometer in the team's metro Charlotte shop. When Johnson and Gordon flip the ignition to start their engines prior to Sunday's 500-mile race, they'll do so with the knowledge that their power plants have passed a test more than three times longer. Hendrick has the capacity to run multiple 800-mile dynamometer races at the same time; Andrews said the team completed its 24th such test of the season on Monday.

It's part of an approach that leaves little to chance, and is built on parts and pieces proving themselves before they're ever placed under the hood. Much like a new car, Andrews said engine parts are apt to showing signs of trouble right after they're built. So the pieces are tested over and over before they're used in a racecar. Many of the engine parts Johnson and Gordon will use Sunday have been utilized in other races this season, giving the Hendrick team a degree of comfort that they're up to the job.

"Our approach here in the Chase is more to pay attention to the components that we're using in the engine in terms of the amount of time they have on them in terms of engine cycles," Andrews said. "Does it have one race on it? Does it have two races on it? Ideally, something new is not necessarily better. Ideally we would like to have run it at one race, taken it apart and looked at it, and for the entire engine and its components that don't get replaced during a normal rebuild to have one or two races on them. If there's anything within a brand new component that's going to give you problems, hopefully it would have cropped its head up the first or second race. Newer isn't always better."

Neither is conservative. Atlanta may be among the toughest tracks on engines -- like Texas and Kansas, it combines high banks and high speeds, and the throttle is open around virtually three-fourths of the racetrack -- and the Chase may be in its waning stages, but Andrews' team won't try to play it safe. Trifling with a proven engine package at this point in the season would actually be a risky move.

"To go in and change something now would almost be detrimental to your routine and your program," he said. "It's not something you would be comfortable with."

So they test, they inspect, they watch and hope. Atlanta in the fall is a perfect storm for extreme engine wear, beginning with something as seemingly innocuous as the weather. Cool, dry conditions like those found in north Georgia in late October are perfect for making horsepower. And then there's the layout of the track itself, with those big, banked sweeping corners that allow drivers to reach speeds of around 200 mph. At Atlanta, drivers race with the throttle fully open around almost 70 percent of the racetrack. Full throttle means the engine is operating at maximum capacity, which places the most heat and stress on the parts within.

"The engine is making its peak power," Andrews said. "It runs at that sustained rate for a longer amount of time than at many other tracks that we go to. Couple that with the fact that your atmospheric conditions get to be very favorable, and you've got a lot of things that start to add up there."

The driver never rests at Atlanta, and neither does the engine. It's always operating at a stratospheric RPM rate, from a high of 9,500 to a low of 7,500. Compare that to last week's event on the short track at Martinsville, where the low RPMs were about 4,800. At Atlanta, pieces never get the chance to cool down. That's why the Hendrick team tries to limit the total number of miles run during the weekend to 700 -- including practice and qualifying -- which is 100 fewer than the engine has proven itself capable of in an in-house test.

"It's a little on the conservative side," Andrews admits. "But it's just where we want to see the mileage on the engine kept in regard to the components and what we've proven out here and feel comfortable with."

But there are always worries, especially at this time of year and on this kind of track. At Atlanta, no one ever takes an engine for granted.

"At this point, we've had Fontana, we've had Lowe's where it was cool out at night running quick speeds around, and it lasted for 500 miles," Johnson said. "We're feeling good about it, but you're always keeping your guard up and keeping some kind of concern for the engine to try and take care of it."