Extension of exhaust manifold conduit into exhaust pipe

A method for manufacturing an exhaust system for an internal combustion engine, comprising the steps of:

• providing a first exhaust manifold conduit having a first downstream portion presenting a first flat side wall, a second exhaust manifold conduit having a second downstream portion presenting a second flat side wall, and wherein each of the first exhaust manifold conduit and the second exhaust manifold conduit includes an inner pipe and an outer pipe disposed around the inner pipe, wherein a space between the inner pipe and the outer pipe extends between pipe ends;
• connecting an exhaust pipe having a body defining an inlet end to the first exhaust manifold conduit and the second exhaust manifold conduit;
• and
• extending the first downstream portion into the exhaust pipe such that a channel within the exhaust pipe is defined by the first flat side wall and the body of the exhaust pipe, the channel communicating with the second downstream portion and wherein the first side wall and the second flat side wall are in confronting relation.

An exhaust system for an internal combustion engine, comprising:

• a first exhaust manifold conduit having a first downstream portion connected to an exhaust pipe;
• a second exhaust manifold conduit having a second downstream portion connected to the exhaust pipe, wherein each of the first exhaust manifold conduit and the second exhaust manifold conduit includes an inner pipe and an outer pipe disposed around the inner pipe, wherein a space between the inner pipe and the outer pipe extends between pipe ends;
• and
• the first downstream portion being displaced from the second downstream portion and wherein the first downstream portion and the second downstream portion converse toward each other.

An exhaust system for an internal combustion engine, comprising:

• a first exhaust manifold conduit having a first downstream portion conveying a first stream of exhaust gas into an exhaust pipe;
• a second exhaust manifold conduit having a second downstream portion conveying a second stream of exhaust gas into the exhaust pipe and wherein the first downstream portion and the second downstream portion converge toward each other;
• means, disposed at least partially within the exhaust pipe, for increasing the lengths of the first exhaust manifold conduit and the second exhaust manifold conduit such that the first stream of exhaust gas and the second stream of exhaust gas flow into the exhaust pipe before merging together;
• and
• means for separating the first stream of exhaust gas from the second stream of exhaust gas.

An exhaust system for an internal combustion engine, comprising:

• an exhaust manifold;
• an exhaust pipe coupled to the exhaust manifold, the exhaust pipe having a body defining an inlet end;
• the exhaust manifold including a plurality of exhaust manifold conduits,
• a first number of the plurality of exhaust manifold conduits each having a first downstream portion that extends into the exhaust pipe,
• a second number of the plurality of exhaust manifold conduits each having a second downstream portion that terminates at the inlet end, wherein each of the plurality of exhaust manifold conduits is made from an inner pipe and an outer pipe disposed around the inner pipe, wherein a space between the inner pipe and the outer pipe extends between pipe ends;
• and
• a plurality of channels within the exhaust pipe, the plurality of channels having a total cross-sectional area that is approximately the same as the total cross-sectional area of the first downstream portions of the first number of exhaust manifold conduits that extend into the exhaust pipe, wherein the first downstream portion and the second downstream portion converge toward each other.