BOVs

[Jay Rabe]

A blow off valve or bypass lets out/loops around a LARGE amount of air.  If 
its enough to pressurize your engine (basically a large air pump,) It is a 
large amount of air.  On a scirocco i built for my brother it has a greddy 
bypass valve vented to atmo.  If you rev the car up quick and let go of the 
throttle the air that gets dumped is enough to push your hand quite a bit 
and does this for a half second, another half second it closes.  And this is 
@ maybe 1psi (not in gear, just revved up.)  It would be much more under 
load and at 15psi.  That would be a lot of fuel dumped into your motor 
washing down the cylinder walls etc. On his car its a rpm/kpa fuel/ign 
system so it doesn't care where any air goes unless its in the intake 
manifold.  Thats why its to atmo.

On a bypass car the pressurized air keeps looping around until the throttle 
is opened again.  No more air goes past the MAF sensor (maybe a little) so 
it doesn't dump much fuel at all during this time.

They both do the same thing, its just what type of system you have that you 
should have a bypass.

You will melt your cat with a bov.  And its not very good for your engine.

The sound and the flames out the exh aren't worth it to me.

---Well maybe the flames with a hollowed cat on a motor you dont care about.

Jay
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