Hollywood stars generally get the run of movie sets. But not Mark Wahlberg and the Bugatti Gran Sport Vitesse sports car used in Transformers: Age of Extinction.

Wahlberg tells USA TODAY that even he had to keep his distance from the 1,200 horsepower machine on Michael Bay's car-filled set. The machine was brought in to play the robot/autobot Drift in car form.

The autobots, or good Transformer robots, might take serious punishment in the computer graphic robot form. But the real cars are treated with kid gloves.

"They don't let you touch it unless you're going to shoot in it, you got to be very careful," says Wahlberg, "It's a very expensive vehicle. They don't have multiples and if something happens there's a problem."

"They got guys on set constantly rubbing them down," says Wahlberg. "When we are not rolling they are protecting them with car covers."

Of course, the machines do take some wear and tear on the action film movie set, especially in scenes shot in a rock quarry (yup, rock quarry, it's a Michael Bay film).

"They rocks spin up and hit the paint, that's like a $600,000 carbon fiber paint job on it," says Wahlberg.

All in the name of art, or at least fast cars and big explosions which propelled the film to $300 million worldwide in its opening weekend. Transformers and the Bugatti look to rock again over the July 4 holiday, already taking pole position.

It's a very different story from Randy Peters, the Transformers transportation coordinator who drove the Optimus Prime Western Star truck in the film. Peters recalled driving through some stunt explosions in the big rig that had an impact.

"You could see the burns in the cars from the explosions, some nicks and scratches," says Peters. "I think everytime you do a Michael Bay film you pretty much put everything to the limit. But if you break something he's not happy."