This mechanical exhaust flap (for subsequent installation) regulates the overall volume of your exhaust system using negative pressure. This exhaust gas flap is open in the presseless and uncontrolled condition. This exhaust flap is closed at idle and at a low speed and the exhaust sounds unobtrusively. The position of the exhaust flap on naturally aspirated engines is determined by the negative pressure that exists in the intake manifold. With turbocharged engines (turbo, compressor), the negative pressure only forms when starting, while driving (without boost pressure) or when idling/shifting. It is advisable to also install a vacuum tank. When the speed increases, the exhaust gas flap opens and the sound of your vehicle opens much louder and sportier. By installing the exhaust gas flap,.
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