Patent ID: 8671671

Claim:
An exhaust system for an internal combustion engine, said exhaust system comprising, in combination: an elongated tube defining a tube interior for receiving exhaust gas from the internal combustion engine; and exhaust flow modification structure within said tube interior having an outer surface spaced from said tube whereby said tube and said exhaust flow modification structure define an exhaust gas flow path surrounding said outer surface, said exhaust flow modification structure configured to produce a laminar flow of said exhaust gas and to modify flow speed of said exhaust gas due to the venturi effect within said tube interior, said exhaust flow modification structure defining an internal exhaust gas flow passageway through which a portion of the exhaust gas in said tube interior flows during operation of the internal combustion engine, said internal exhaust flow passageway configured to modify flow speed of the portion of exhaust gas due to the venturi effect, and said exhaust flow modification structure including a first structural component and second structural component, said first structural component having an inner surface defining said internal exhaust gas flow passageway, said inner surface configured to form an internal venturi having a converging inlet nozzle portion, a diverging outlet diffuser portion and a gas flow restricting throat portion interconnecting said converging inlet nozzle portion and said diverging outlet diffuser portion, and said second structural component comprising a double-ended member having a smoothly curved outer surface projecting outwardly from said converging inlet nozzle portion and defining an annular airflow space therewith for enhancing the venturi effect of the flow modification structure.