Well... Normally the Charged air goes through that hole and up to the diaphragm. the OTHER side of the diaphragm has air from the Intake manifold (other side of the throttle plate)..
WHEN your throttle plate is WIDE OPEN, and BOOSTING then the 2 pressures are the same. Once you CLOSE the throttle, the becomes a vacuum on the one side and High pressure on the other.. So The Valve OPENS and releases air.
I GUESS the idea behind this mod.. is so that the Valve DOES NOT open under HIGH boost.
because EVEN though! AT your turbo there may be 25psi, but because of how much piping there is between the turbo and intake manifold you can lose partial or whole PSI... Hence you would have 25psi on one side of the BOV diaphragm and 24.5psi on the other... and OPEN your BOV very slightly. (it can ALSO make your boost Flutter under extreme situations)
SOo by him venting the diaphragm to atmosphere the valve will not open till the intake manifold reaches a vacuum (anything LESS than atmospheric PSI) I would think it would make the Compressor Surge EVERYTIME you shift, atleast a little.
My OPINION.. dont do it unless you are experiencing Fluttering Issues. and are broke as hell... And have a knack for messing things up.
Im just giving examples. I DO not know if your car DOES or DOESNOT have 25psi @ the turbo
Topic: $0.16 Blow off valve mod (Read 1205 times)