The Fast and the Furious isn't just a macho action-thriller about speedy autos and the hunky men who drive them. And that was bad news for star Paul Walker — who plays an undercover cop romancing Jordana Brewster in the flick (skidding into theaters Friday).

"I had to do a love scene with Jordana [and] she was dating Mark Wahlberg at the time," he tells TV Guide Online. "And there was a rumor that he wanted to be on the set the day Jordana and I locked lips. I kept looking around to see if he was there. I admit I was a little nervous, but it was cool: Mark never appeared and Jordana was a complete sweetheart. The only downside was hearing the crew snickering while we were trying to get it on."

Walker felt a little more comfortable cozying up to the film's other stars — the cars. "I grew up around them," says the 27-year-old

Varsity Blues actor, whose Fast character is investigating the dark side of drag racing. "My grandfather used to race, so I was brought up on souped-up Fords and Chevys. I've always been into what's under the hood." Walker admits that the carefully planned racing stunts in the movie don't quite match the real-life adrenaline rush he's been getting on a race track near Los Angeles. "I wasn't that familiar with imported cars before I did this film, but now I've actually bought one myself," he says. "I had to import it — it's like the Ferrari of Japanese cars. I've been racing on a drag-strip in Palmdale and I've won every time. It's a great feeling. I've been up to 160 or 170 mph!"