In a tiny, rented-out editing room tucked away in Building 9 on the Warner Bros. lot, director Eli Roth is bouncing off the walls.

He’s just learned that the MPAA ratings board has approved a gruesome poster of skinned wild boar meat that went up in theaters over the weekend plugging “Hostel: Part II,” which doesn’t open until June 8, but is already getting plenty of buzz.

The man with him, veteran editor George Folsey Jr., shakes his head in surprise.

What the MPAA will clear with this type of film is always a dicey proposition. Roth and a cadre of fellow directors — all closely knit, young and well-educated — are introducing a level of terror, torture and depravity that would make Freddy Krueger run for cover. Audiences are lapping it up, with the low-budget films routinely beating studios’ pricey entrants at the box office.

This team of helmers is called “The Splat Pack,” a term recently coined by critic Alan Jones in Total Film, for their dedication to the genre, which they say has been hijacked by watered down PG-13 fare. Two of the most successful of these raw horror franchises, Lionsgate’s “Saw” and “Hostel,” revolve around people doing unspeakable things to themselves and others, like burning a face off with a blowtorch and then clipping off the dangling eye with a scissors. (Screen Gems is partner on the “Hostel” pics.)

The other filmmakers in the group are Alexandre Aja (“The Hills Have Eyes”), Darren Lynn Bousman (“Saw II” and “Saw III”) Neil Marshall (“The Descent”) and James Wan (“Saw”). There’s also scribe Leigh Whannell, who came up with the idea for “Saw” with Wan and penned all three of those pics. Serving as something of mentors are subversive looking rocker-director Rob Zombie (“The Devil’s Rejects”), Quentin Tarantino and Guillermo del Toro.

“We all have the same agenda: to bring back really violent, horrific movies,” says Roth, a New England native who has the looks of a leading man and is the son of a Freudian psychoanalyst who teaches at Harvard.

It made sense for Roth and the others to band together, share trade secrets and offer guidance. By their own admission, they are film geeks who’d rather extol directors like Wes Craven than Martin Scorsese. They get together when they can, and there is a friendly rivalry and a sense of one-upsmanship.

While Bousman was shooting “Saw III,” Roth told him over the phone about an amazing scene he’d just written for “Hostel II.” It was too late. Bousman had just shot the same scene.

“I don’t care if everyone looks down on us,” says Whannell, reached by phone in Melbourne, Australia, where he is spending the holidays. “What do I get out of it? I get to know that I’ve contributed to pop culture, which is amazing.”

By and large, the fresh-faced and enthusiastic helmers go unrecognized by the press and Hollywood establishment, which has long considered horror the bastard stepchild of the movie business. The men in the group still feel like outcasts as they make their movies for indies like Lionsgate or studio genre labels. Of course, they are heroes among horror fans, who consider the director the star, not the actors, a distinction any auteur craves.

Charming and with a quick wit, Roth made home movies throughout his youth, when he admits he was obsessed with blood and gore.

Whannell has an insatiable curiosity about everything except math, and took up with the more introverted Wan when the two met at film school in their hometown of Melbourne. Looking to make the cheapest movie they could upon graduating, they put two guys in a bathroom with a chainsaw, and “Saw” was born.

Bousman was a frustrated writer who toiled away as a production assistant, unable to drum up any interest in his scripts. So he decided to write the most offensive, violent screenplay he could, appropriately calling it “The Desperate.” It got him a meeting with Twisted Pictures, producer of the “Saw” franchise. Some of his material from his script was used in “Saw II,” which Bousman directed.

Their films cost next to nothing to make. Yet they mint gold.

Last fall, “Saw III” opened at No. 1 with $33.8 million, before going on to gross $80.2 million at the domestic box office. That’s more than studio fare like “World Trade Center” and “Miami Vice.” “Hostel” grossed $47.3 million in its run last year, better than more mainstream suspense fare like M. Night Shyamalan’s “Lady in the Water.”

As with every successful trend in Hollywood, the question is how long it will last. But unlike, say, sci-fi or action pics, with horror pics there is only so far you can take things before the ratings board steps in and threatens to slap a picture with an NC-17.

“It is getting harder and harder to get stuff past them,” says Twisted Pictures’ Mark Burg, who produces the “Saw” franchise with partner Oren Koules. “One or two movies like this, they let go up. But the ante has been upped, whether by the types of death or body count or torture scenes. They’re just waiting for Eli to show up with ‘Hostel II.’ ”

Roth and Lionsgate were worried that the ratings board, which doesn’t like open wounds and blood, would challenge the “Hostel II” boar poster. At the same time, how could they forbid it, since it is really just a piece of meat?

At Lionsgate, co-prexies of marketing and publicity Tim Palen and Sarah Greenberg have turned the selling of horror pics into an artform. Palen, also an accomplished photographer, came up with the idea for the “Hostel II” poster and drove to a slaughterhouse in Simi Valley, Calif. (For “Saw III,” he procured blood from star Tobin Bell and used it in a limited run of posters).

When the ratings board threatened to slap “Saw III” with an NC-17 rating, Bousman grew depressed and dejected. Then he called Zombie, who had his own MPAA problems with “The Devil’s Rejects.” Zombie advised Bousman to speak personally to the ratings board and explain his reasoning, like any other filmmaker.

“Only a filmmaker can eloquently say why someone is getting tortured or massacred. It’s not just exploitive,” says Bousman. “Take the scene of a naked woman being tortured. The ratings board just saw torture and nudity, they didn’t see the raw emotion. I, as the filmmaker, could explain that. At the end of the day, they agreed.”

Bousman still had to make other cuts, including 12 minutes at the beginning of the pic. In the scene, a man wakes up to find his body covered in piercings. He has to rip out the piercings if he wants to escape before a bomb goes off.

Zombie says the combo of violence and sexuality is a “hot button” for the ratings board. In “Devil’s Rejects,” there is a scene in which a woman is getting pistol-whipped and humiliated in a hotel room. Even though there was no nudity, the MPAA objected, saying the tone was too dark.

“My movies are supposed to be shocking and horrible. I don’t want it to be fun,” says Zombie, who is prepping a remake of John Carpenter’s “Halloween” for Dimension. “When they would suggest certain cuts, I said, ‘Look, you are trying to make it OK by making it less horrible. It should be horrible and uncomfortable.’ ”

Roth says the ratings board shouldn’t worry, since no one going to see his movies will expect anything other than what they are.

He discovered that with what is regarded as the first of the Splat Pack movies, “Cabin Fever,” which Lionsgate snapped up at the Toronto Film Fest in 2002. The movie, about a group of kids overcome by a flesh-eating disease, was a sleeper hit. Pic even captured the attention of Tarantino, who befriended Roth and showed him the ropes.

The movie helped establish Lionsgate as the home studio of this group and their films, and execs there make no apologies. Prexy of acquisitions and co-productions Peter Block and prez of theatrical films Tom Ortenberg are both horror aficionados.

Other companies have their own wizards of the genre, such as Clint Culpepper at Screen Gems, Andrew Rona at Rogue and Bob Weinstein at Dimension (whose Dec. 25 opener “Black Christmas” is the very definition of counter-programming).

There’s a new moniker being used to describe the ultraviolent horror movies — “gorno,” a combo of gore and pornography.

Roth hates the term.

“I find the whole notion of torture porn insulting. People assume these are movies made by idiots for idiots. They’re not. These films are very subversive,” Roth says. “Art Forum magazine said that ‘Hostel’ was the smartest film in terms of being a metaphor for the Iraq war and America’s attitude overseas.”

The directors are being approached by the studios to make more mainstream horror films. For a time, Roth was attached to a remake of “The Bad Seed” for Warner Bros., but then he got caught up with “Hostel.” It’s doubtful whether the majors would really go for the jugular and make the kind of movies Roth and his cabal make.

“They wouldn’t know what to do with me,” Roth says.

Even Screen Gems, part of the Sony empire, gave “Hostel” to Lionsgate to market and sell, reportedly concerned about content.

And if studios did decide to make an ultraviolent movie, marketing execs would likely panic during test screenings. If a horror movie is worth its weight, people will actually recommend that others not go see it, the exact opposite of what studio honchos want to see when they evaluate test scores.

But they’re good investments. Roth jokes that the combined cost of “Cabin Fever” and his two “Hostel” pics wouldn’t pay half the salary of a star in “Ocean’s Thirteen.”

Such comparisons will be ever more apparent on June 8, when “Hostel II” opens against “Ocean’s.” It’s a matchup Roth already has dubbed the Rat Pack vs. Splat Pack.