"Sex Drive" is a "Sure Thing" for the "Superbad" generation.

It's a road trip comedy about a teen driving 800 miles to lose his virginity after an Internet hook-up with a girl who may or may not be as hot as her Web photo, but who has promised to "go all the way."

So no, it doesn't really have the charm of the romantic comedy that John Cusack (a star) and Rob Reiner (a star director) had back in '85. But if it lacks much of "The Sure Thing's" warmth and romance, "Sex Drive" makes up for that in goofy, no-holds-barred raunch.

Because dorky Ian (Josh Zuckerman) has that one cocky, sex-obsessed pal, Lance (Clark Duke as sort of a slightly thinner Jonah Hill) along for the ride, there to coach him, to lead by example (sexual conquests along the way), to teach Ian "the ability to close" — the deal, that is.

The problem is that the just-out-of-reach BFF Felicia (Amanda Crew, quite good) invites herself along. She's got a crush on Lance, whose arrogance, and ready cash, are catnip to the ladies. Ian has had a crush on her forever. Pity he can't escape her "friend zone."

Misadventures pile up on our trio as they Ferris Bueller their way from Chicago to Knoxville, Tenn.: car mishaps (racing their '69 GTO on the Interstate — not smart), a dalliance with a convenience store clerk, encounters with a must-be serial killer hitchhiker and a hard-partying community of Amish folk, led by a very dry Seth Green.

"Whatup, English?"

Bit players around the edges of this messy and overlong trek are what make the trip work. Green is one. James Marsden is another. The "Enchanted" and "Hairspray" star should be too old to play Rex, the bullying older brother, but he hurls himself at the GTO-owning, teasing thug with such verve you won't see a hint of Prince Edward in him.

Co-writer/director Sean Anders flings a lot of stuff at the screen — every indiscretion the kids commit turns up on somebody's Web page. But he's working with a charisma-deprived leading man and a script that doesn't allow much room for heart. And you could feel the air sucked out of the theater about the time the roadkill euthanasia scene pops up.

Still, there's a reason "The Sure Thing" worked, and that borrowed message — that it isn't about "closing the deal," objectifying the many nubile and often naked women who cross his path, in short, being like Lance — still sings.

It's too bad the clutter around that theme almost drowns it out in "Sex Drive."