Exhaust manifold of a multi-cylinder internal combustion engine

Abstract

A heat-insulating, light and vibration-proof exhaust manifold for a multi-cylinder internal combustion engine is provided. The exhaust manifold comprises an upper stream flange, a lower stream flange, four manifold pipes at an upper stream, a manifold chamber (gathering section) at a lower stream and a manifold case of a plate metal covering the manifold pipes and the manifold chamber. The manifold pipes have upper stream ends to be connected to exhaust ports of the internal combustion engine through the upper stream flange and lower stream ends gathering in the manifold chamber. Upper stream ends of the manifold pipes and the manifold case are welded to the upper stream flange, and lower stream ends of the manifold chamber and the manifold case are welded to the lower stream flange. The manifold pipe and the manifold chamber can slide relatively at a slide portion which is maintained by pressing the manifold chamber and the manifold case against the manifold pipe.