How does a BOV work?
 

How is the valve actuated and what regulates the release pressure?

-Icarus

Re:How does a BOV work?
 

the valve is actuated by the vacuum created when the throttle plate closes. what do you mean by release pressure. some bov's are adjustable as to how much tension is on the spring inside it

Re:How does a BOV work?
 

Imagine a plate, the vacuum hose from your intake plenum is pushing on one side and the pressure from your charge line (line from turbo) is on the other. When you close your throttle plate (take your foot off the 'gas') pressure is still in your charge line but no longer in your intake plenum. This will push the plate and allow the compressed air to expel into the atmosphere, or back into the turbo intake which every you have.

Another type of BOV, usually aftermarket ones use an adjustable spring intead of a line to the intake plenum, they work the same way.

Re:How does a BOV work?
 

i have the same question about the hks ssqv pull type bov, but not even hks can answer the question as to how it works
i have no respect for hks

Re:How does a BOV work?
 

http://jekylandhyde.madpowaz.com/bov.htm

it's a write up on the oem MR2 valve, the principle for which is the same used to design valves like the SSQ, apex twin chamber, etc.

i have reservations about the accuracy of the description of how it works because it seems the author doesn't take into account the pressure on the valve itself inside the charge pipes, only the pressure in the chambers. that said, it's still a better write up than i could do on short notice.

i have an apex twin chamber i'm thinkin about pulling apart though, just to be sure..