A Blowoff Valve (BOV) is a device used in turbocharged engines to release excess pressure from the intake system when the throttle is closed. This helps prevent compressor surge, which can damage the turbocharger and reduce performance. The BOV opens to vent the pressurized air, creating a distinctive sound often associated with performance vehicles. Typically made from metal or plastic, a BOV can be adjustable or fixed, depending on the design. It is commonly found in vehicles equipped with a turbocharger and is an essential component for maintaining engine efficiency and longevity. Properly functioning BOVs contribute to smoother acceleration and improved throttle response.