Blow off Valve Question>

How exactly is the sound of a blow off valve created?

My friend says that everytime you release off the acceleration/gas the pressure is released, and therefore creates the "BLOW OFF VALVE SOUND". Another friend argues that the pressure is released, and the sound is created, as you shift gears, or let off the clutch.

Can someone correct/answer? Thanks :)

pressure relief.......

Originally posted by config
How exactly is the sound of a blow off valve created?

My friend says that everytime you release off the acceleration/gas the pressure is released, and therefore creates the "BLOW OFF VALVE SOUND". Another friend argues that the pressure is released, and the sound is created, as you shift gears, or let off the clutch.

Can someone correct/answer? Thanks :)

You just said the same thing twice. The actual way it sounds depends on the desing of the BOV.

When you let off the accelerator to shift the throttle plate closes. This creates backpressure and can be very damaging to a turbo so that is why they have Blow Off Valves and Diverter Valves. The sound you're hearing is the Blow Off Valve releasing that pressure into the atmosphere.

So, you hear the sound, every time someone shifts, correct?

Not all the time. Only when positive pressure is built to a point that will open the BOV valve. You can adjust them.

Originally posted by config
So, you hear the sound, every time someone shifts, correct?

When you take your foot off the gas.