Canadian filmmaker Ron Mann (Grass, Go Further) may be more a fan of pop culture than a critic, but he’s also a closet art historian, as evidenced by this documentary about the eccentric and influential hot-rod designer and outsider artist Ed “Big Daddy” Roth. Seeing Roth’s goofy imagery in everything from comic books to beach party movies to the shapes of electric guitars, Mann enlists writer Solomon Vesta to adapt Roth’s prose as narration, John Goodman to deliver the result, and Michael Roberts to turn Roth’s visions into animated cartoons. Some of Roth’s cars become characters, their voices furnished by Ann-Margret, Jay Leno, Brian Wilson, Matt Groening, Tom Wolfe, and others. The pace never flags, and the enthusiasm is infectious. 76 min. a Gene Siskel Film Center.