BOV is an acronym that stands for "Blowoff Valve," a device commonly used in internal combustion engines, specifically turbocharged or supercharged engines. It is principally designed to release excess pressure from the intake manifold when the throttle is abruptly closed, preventing damage to the turbocharger and other components.
A blowoff valve plays a crucial role in the functioning and protection of a forced induction system. When the throttle plate closes, causing an instantaneous drop in intake manifold pressure, a surge of compressed air can be forced back into the turbocharger. This phenomenon, known as compressor surge, can lead to harmful effects such as stalling or damaging the turbocharger bearings. A BOV provides a controlled path for the excess pressurized air to vent to the atmosphere or back into the intake system, preventing compressor surge.
Commonly found in high-performance and modified vehicles, a BOV consists of a valve mechanism and a spring that determine when it opens and closes. When the pressure difference across the valve reaches its set level, the BOV opens, allowing air to escape. The distinctive sound often associated with turbocharged cars, the "whoosh" or "flutter" sound, is a byproduct of the BOV releasing excess pressure.
In summary, a BOV is an essential component of forced induction systems, protecting the turbocharger and engine from damage by safely venting excess pressurized air when the throttle is closed rapidly.
