Double-walled exhaust manifold for motor vehicle, has inner unit delimiting insulation cavity with outer unit, and including two straight upstream tubes with secondary ends slidably fitted with intermediate parts of sliding downstream tubes

摘要

The manifold (10) has an inner unit (12) with sliding downstream tubes (16, 18) and delimiting an inner insulation cavity (20) with an outer unit (14). The unit (12) has two straight upstream tubes (22) whose primary ends (24) are arranged in the extension of an exhaust line, and secondary ends (26) are slidably fitted with intermediate parts (28) of the tubes (16, 18) having an axis (B) intersecting an axis (A) of the tubes (22). The outer unit is molded from a single piece, around the inner unit. The sliding downstream tubes are fitted into each other. Independent claims are also included for the following: (A) a method of manufacturing an exhaust manifold (B) an internal combustion engine comprising a cylinder head and an exhaust manifold.