Regular beauty version, special shaped valve style A plum-shaped exhaust cutout, sometimes called a "plum-shaped exhaust valve," is an aftermarket automotive modification designed to change the sound and performance characteristics of a vehicle's exhaust system. It is essentially a valve or gate that can be installed in the exhaust pipe to allow for on-the-fly adjustments to the exhaust flow, particularly the level of noise and backpressure. Track or Racing Use: Some car enthusiasts use exhaust cutout s primarily for racing or track days. Opening the cutout can provide a performance boost, and the louder exhaust note can be useful for communication among drivers on the track.
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