SAM DEAN The Roanoke Times

Denny Hamlin crosses the finish line to win the TUMS Fast Relief 500 last Sunday at Martinsville Speedway, as John Andretti (34) recovers from a crash. As the winner of the race, Hamlin's car was inspected at NASCAR's Research and Development Center Tuesday.

CONCORD, N.C. -- It's 7:45 a.m. Tuesday. School buses clutter local roads. The sun climbs over the horizon.

The front doors to NASCAR's research and development center are locked.

Not for long.

They swing open. You enter and walk through a pass code protected door, by offices, cubicles and conference rooms and down a hallway. You go through a pair of wide doors where a sign that warns of the need for safety glasses, down another hallway and through another set of wide doors.

Finally, you see Denny Hamlin's winning car from last weekend's Sprint Cup race at Martinsville. There's Jimmie Johnson's second-place car, along with the cars of Kurt Busch and Mark Martin. NASCAR officials are about to begin their extended post-race inspection. Even if a car passes inspection at the track after the race, it can be penalized if a violation is found here.

An added benefit to winning -- beyond the money, points and glory -- is that the winning team goes through inspection first. Members of Hamlin's team, under NASCAR observation, pull the engine from his car to be torn down.

This used to occur at the track, but NASCAR moved some of its post-race inspections to its R&D Center. They didn't have to wait for the engines to cool as they did after a race and NASCAR had more precise equipment to measure cars and engines.

Series officials can get to within about an eighth of an inch with measurements at the track. At the R&D Center, officials can get to within thousandths of an inch. That helps NASCAR try to keep the competition balanced and fair.

For as much as NASCAR looks for violations, it also studies what teams do with their cars and engines.

"We will do some additional inspections from time to time with some of the parts ... such as crankshaft weights where we may not have a rule in place now but it allows us to keep track and monitor a direction a team may be headed,'' said Kenny Lawson, supervisor of NASCAR's engine inspection department.

As the engine is dissected, Hamlin's car is pushed to another garage bay for its once-over. Crew chiefs often accompany the inspection, although Mike Ford is not. Instead, the team has its car chief, an engineer and a couple of fabricators.

Busch's car follows Hamlin's. NASCAR inspects the engines of at least the first- and second-place car each week at the R&D Center, along with a randomly selected car. The winning car and at least one random car are inspected each week. Johnson's and Martin's cars have been regular visitors the last month after NASCAR warned them they were coming close to the tolerances earlier in the Chase.

Busch is here as the random. The crew chief of the first car out of a race is asked to pick a finishing position -- often 1st through 26th, although during the Chase it could be first through 12th. The car that finishes there must go through the same inspection process as the winning and second-place teams. That's why Busch, who finished 17th, is here.

Hamlin's car is in place. All the cars are put in the same position the rear slightly tilted up. A NASCAR inspector uses a Romer Arm -- which sounds like R2-D2 with its beeps and squeaks and looks like three narrow tubes hooked together.

There are about 10 radio frequency ID tags placed on the chassis underneath the body. Any new car must be certified and have those ID tags placed for the Romer Arm to pick up the signal. Any changes to that part with the tag will kill the signal and officials will know something has been adjusted.

"Once the chassis has been certified, there's nothing you can do to that chassis that can gain you a competitive advantage,'' said Billy Berkheimer, NASCAR's senior manager of template inspections.

An interlocking series of body templates -- nicknamed a claw because that's what it looks like -- is draped over the car's body. The car goes through this before it goes on the track and again at the R&D Center. This process can help determine if a car is beyond the legal limit because of on-track contact or if it's done on purpose.

Other points on the car are then checked with the Romer Arm, including spots on the splitter. A large screen that hangs from the ceiling displays the results and how close a team is to the limits. More than two hours after the inspection started, Hamlin's car passes. So do the other cars.

"When you see that process it takes any doubt out of your mind that you would want to fudge the rules,'' said Drew Blickensderfer, crew chief for Matt Kenseth. "It's going to get caught there because of how tight the tolerances are and how they go over every little detail.''

Every Tuesday morning, the process begins again.