Abstract: In a preferred embodiment, a log-type intake manifold for a diesel engine has a longitudinal passage with four equally spaced lateral outlet openings on one side and a centrally disposed inlet opening on the other side of the passage. Similar outlet flow conditions are created in the outlet passages by the addition of at least one flow directing vane at an outlet toward one end of the passage from the inlet to redirect the outlet gas flow into a pattern similar to that of the naturally occurring gas flow patterns at the outlet openings located toward the other end of the passage from the inlet.