ART : Artist or Patron: Who’s in Driver’s Seat? : Hiro Yamagata tries to transform his image with a show of decorated vintage Mercedes-Benzes at struggling Municipal Art Gallery.

An advertising blitz for a wealthy artist known mainly for his phenomenal success in the commercial print business and for his philanthropic activities has raised eyebrows in the art world.

Ballyhooed on banners all over town and on a Sunset Strip billboard, Hiro Yamagata’s “Earthly Paradise” opens to the public Sept. 13 at the Municipal Art Gallery featuring a series of fully restored 1950-52 Mercedes Benz Cabriolets whose exteriors are painted with tropical landscapes.

The promotional efforts are so out of whack with what usually goes on at the city-owned, poverty-stricken gallery that many art aficionados suspect a payoff.

Not so, according to the artist and exhibition curator Ed Leffingwell, who agreed to the show in 1991 when he was director of the gallery. Yamagata has given a $250,000 grant to a private support group that retains Leffingwell and supports exhibitions at the Muni and other local institutions, but that gift was made a year after his exhibition was booked, Yamagata says, and the money is being used for other projects. He is paying all expenses for “Earthly Paradise.”

And how much is that? He throws up his arms and rolls his eyes in response to the question.

Yamagata, a 46-year-old artist who was born in Japan and has lived in Los Angeles since 1978, is an energetic, personable fellow who has lots of friends in high places but appears quite guileless. Without prompting, he readily admits that he hasn’t been taken seriously by art people who matter.

“I have tried to show my work in museums, but everyone says, ‘You are too commercial’ or, ‘You are a shopping-center artist,’ ” he lamented during a recent interview in his Malibu studio.

He and his well-connected promoters, notably dealer Fred Hoffman, say that the show is an attempt to transform Yamagata’s image as an artist. He has made a fortune by producing wildly popular prints for Martin Lawrence Limited Editions Inc. Galleries. Indeed, he was the firm’s hottest seller until 1990, when his contract expired. But the deal confined him to commercial publishing, Yamagata said. “It was a Catch-22, or maybe a Catch-44.”

In the meantime, he has emerged as a generous philanthropist who supports the arts, education and AmFAR’s campaign for AIDS research. Priding himself on taking quick action while others only talk about problems, he has garnered admiration in rarefied circles of politics, society, show business and even at Los Angeles’ Museum of Contemporary Art and New York’s Museum of Modern Art, where he has funded major exhibitions.

But now Yamagata hopes that “Earthly Paradise” will change the image of his work in the art world.

Beginning with a splashy private party on Friday night (honoring Elizabeth Taylor for her contributions to AIDS research), the show is being promoted as Yamagata’s “first major American museum exhibition.” A worldwide tour including sites in America, Europe and Japan is in the planning stages.

The idea behind the lushly painted cars is to merge beautiful examples of technology with the presence of nature, Yamagata says. “I’m not talking about ‘Back to Nature’ or ‘Save the Earth.’ ” Instead, he asks viewers to pay attention to wonders of nature that are all around them--in drops of water, rainbows, skies and gardens.

To make the point, he and about 20 assistants are painting collage-like images--mostly derived from photographs Yamagata has taken in Fiji--on vintage automobiles that he has salvaged and restored. Eight cars--six fully painted and two in process--are in the Muni exhibition, but ultimately he plans to complete two dozen.

Yamagata credits art patron Stanley Grinstein with making the connection that led to the Los Angeles show. They met through a mutual friend, the late composer John Cage, according to Yamagata, and worked together on a local presentation of an Andy Warhol documentary film. Grinstein--a longtime member of the Directors of LAX: The Los Angeles Exhibition, a private group that was founded to support the Muni but currently has no formal connection to the gallery--suggested that Yamagata take his exhibition proposal to Leffingwell.

“He went nuts,” Yamagata says, recalling Leffingwell’s response to models of the project.

Confirming that he accepted the show on its aesthetic and conceptual merit, Leffingwell says: “I’m always interested in the interface between popular culture and fine art.”

Furthermore, he says, “Earthly Paradise” is “in the lineage of other car shows,” such as past exhibitions at MOCA and the Laguna Art Museum.

* Hiro Yamagata’s “Earthly Paradise” opens to the public on Sept. 13 at the Los Angeles Municipal Art Gallery, Barnsdall Art Park, 4800 Hollywood Blvd. Hours are Tuesday-Sunday, 12:30 p.m.-5 p.m. Admission: adults, $1.50; children under 12, free. Information: (213) 485-4581.