Patent ID: 6263669
Filing Date: 2001-07-24
Classification: F01N,F02B,Y02T

Abstract:
An exhaust manifold for an internal combustion engine comprising:first, second, third, and fourth runners, each runner having upper and lower ends, wherein the runners are secured at their upper ends to a cylinder head;a mixing pipe surrounding the lower ends of the runners;the lower ends of the runners being connected to the mixing pipe in a substantially longitudinal direction such that exhaust gases are introduced into the mixing pipe without colliding with the inner walls of the mixing pipe;the first and second runners being joined to each other over a connecting portion at their lower ends prior to connection with the mixing pipe;the third and fourth runners being joined to each other over a connecting portion at their lower ends prior to connection with the mixing pipe;at least one crescent shaped exhaust flow guider formed integrally with the connecting portion where the first runner joins the second runner and where the third runner joins the first runner; andthe runners having an oval cross section at their upper ends and transitioning to a circular cross section at their lower ends.