EXHAUST SYSTEM FOR AN INTERNAL COMBUSTION ENGINE

摘要

The invention relates to an exhaust system (10) for an internal combustion engine (20) comprising a number of cylinders (1, 2, 3, 4) with a preferably one-piece exhaust pipe assembly with at least one first exhaust pipe (11, 12, 13, 14) per cylinder (1, 2, 3, 4). Two first exhaust pipes (11, 14; 12, 13) of both cylinders (1, 2, 3, 4), which do not immediately follow one another in the firing order, lead into a second exhaust pipe (15, 16), and two second exhaust pipes (15, 16) lead into a common manifold (17). The invention provides that, in the opening area (21, 22, 23) of both first and/or second exhaust pipes (11, 14; 12, 13; 15, 16), the uniting first and second exhaust pipes (11, 14; 12, 13; 15, 16) span an angle (a₁, a₂) = 30°, preferably = 20°, said angle (a₁, a₂) being spanned by the tangents (t₁, t₂, t₃, t₄) at reference points (P₁, P₂, P₃, P₄) of the inner wall (11a, 14a; 12a, 13a; 15a, 16a) of the exhaust pipes (11, 14; 12, 13; 15, 16). These reference points (P₁, P₂, P₃, P₄) are defined by an amount (a₁, a₂), which is approximately half the diameter (d₁, d₂) of the first and second exhaust pipe (11, 14; 12, 13; 15, 16), upstream from a first points of intersection (S₁, S₂) of both tangents (t₁, t₂, t₃, t₄).