Pit lane on race day is an adrenaline rush. Especially on Sunday at the 100th run of the Indianapolis 500, where the seats are sold out and the stakes are high.

IndyCar pit crews have just seconds to change four tires and refuel their driver's car, all while other cars fly past. In this line of work, members of pit crews expect to get pretty banged up.

The Toyota Grand Prix of Long Beach is one of the big races in California that leads up to Sunday's Indy 500. That's where I met Graham Rahal's pit crew — one of the top crews in pit lane.

These six guys live and breath racing. Adam Kolesar, Heath Kosik, Kyle Sagan and crew chief Donny Stewart change the tires. Mark Mason mans the airjack and Mark Bruce is the team's fueler.

They're packed tight in the pits. It's close quarters down here. Heath Kosik says that one misstep can cost a race — or worse. He once had a driver nearly run him over.

"He ran right through our box, ran over our equipment and I had to basically jump on top of the car," Kosik says.

Over the years, cars have swerved, slammed and pummeled crews.

There was an incident in 1999 where driver Michael Andretti accidentally ran over his own crew member who was standing in front of his back wheel. Then, three years ago in Sonoma, Scott Dixon, who was in the lead with 15 laps to go, was penalized after he clipped another driver's crew member. (Dixon lost the race and maintains that the rival team's pit crew purposely got in the way.)

Last year on a rainy day at NOLA Motorsports Park, Francesco Dracone lost control and slammed into his own crew chief. And at the 2015 Indy 500, a collision in pit lane sent a car fish-tailing into two guys changing tires.

Everyone in pit lane has a story of their own.

On Rahal's team, Mark Mason is the veteran down here. He's been in the pits for decades and he's got the scars to prove it. He tells me his favorite story took place on race day back in the '90s.

"We're all out on pit lane," Mason says. "And the cars are coming in at massive speed."

Whoever changed the tire on the other team's car didn't fasten the wheel nut tight enough.

"By the time their car got to us, it spat the wheel nut off and hit me clean on the shin," he says. "It was like a bullet."

For pit crews, these high-speed injuries are just part of the job. They're here to win — even if that means almost catching on fire.

Mark Bruce is the team's fueler. The hose he plugs into the side of Rahal's race car pumps in three gallons of fuel per second. One time, he says, his fuel line broke open.

"So it was just pouring fuel out of the side of the car," Bruce says. "I was soaked, my legs were soaked."

When it hit the exhaust, the car ignited. He escaped the flames, but it was close.

"Knock on wood, I've never been on fire," he says.

That's why IndyCar has fire teams stationed at each pit box, like Edward Ross and Pit Fire co-chief Cathy Shumaker.

"Last year I was at a race where somebody broke his leg," Shumaker says. "Remember that? We were at Fontana. Somebody broke his leg in the pit — where he got hit by his own car."

"Yes, it's the part of racing you never want to see," Ross says. "People know the risks. This is a dangerous sport."

Back in Graham Rahal's pit box, team manager Ricardo Nault jumps on the radio:

"Box, box, box, Graham! Box, box, box!"

That's the call to pit. The crew throws off their headsets and puts on their racing helmets. This is their moment in the spotlight.

Mark Mason crouches against the wall with the airjack, Mark Bruce clutches the fuel line and the wheel guys fire up the air guns.

Graham Rahal's pit crew is ready and waiting.

Ricardo Nault radios to his team as the car flies into the pit box: "Nice and smooth, gentlemen."

There's a burst of activity. The car is jacked up and the red-hot, chewed-up tires come off. Meanwhile, the fuel hose goes in and fills the tank. New tires go on, the fueler unplugs and the air jack is released.

The moment Rahal's wheels hit the ground, he hits the throttle. The pit stop lasts just 6.7 seconds.

"Alright, clear out," Nault says over the radio.

Sunday's Indy 500 is a total sellout event. The 500-mile race will last hours — but those heated moments in a pit stop could very well determine the race.

For Mark Mason, that's exactly how he likes it.

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