| 摘要 |
<p>A vehicle internal combustion engine exhaust system (1) featuring two different exhaust routes (11, 12) to which the exhaust gas is directed selectively by an on-off device (16); the system (1) also comprising a device (21) for comparing parameters, consisting in engine speed, the opening angle of the throttle, and the vacuum inside the intake manifold (3) and/or engine load, with respective predetermined values, for opening the on-off device (16) upon the above parameters reaching the aforementioned predetermined values, and so selectively enabling the exhaust gas to flow along both the exhaust routes (11, 12). <IMAGE> <IMAGE></p> |
