An exhaust manifold apparatus for routing an exhaust gas produced by an internal combustion engine is described. The manifold includes a manifold log with a log wall that defines a log bore. The log bore is in fluid communication with an upstream opening of the manifold log and a downstream opening of the manifold log. An inlet runner includes a runner wall that defines a runner bore in fluid communication with the log bore. The inlet runner is engaged to the manifold log at a stress point, which also includes at least one stiffening rib disposed on an interior surface of the log wall and/or the inlet runner wall.