bypass valve

[Joshua Van Tol]

>In a message dated Thu, 8 Feb 2001  6:24:35 PM Eastern Standard 
>Time, Joshua Van Tol <josh at spiny.com> writes:
><<
>Nope, they're in the right way. The inlet is in line with the 
>vaccuum hose connection, and the outlet is at 90 degrees to the 
>other two. If they were in wrong, they'd never open.
>  >>
>
>    You are incorrect in your description, the inlet/boost side 
>should be perpendicular to the vacuum inlet as in the factory 
>installation.  The way Dahlback has installed them is backwards, and 
>will cause them to leak under higher boost levels.  The only thing 
>keeping them closed is about a 5 lb spring and intake manifold boost 
>thru a 3mm vacuum hose, not much.
>Javad

Yep, you're right Javad. I did some more looking and indeed the way 
you describe it is the usual way they're installed. I'd tend to think 
though that with a properly installed manifold vacuum/boost source 
that it could work the other way too, and probably open quicker on 
throttle lift. Perhaps the Dahlback car has a huge throttle body, and 
experiences almost no drop from manifold to bypass valve?
-- 
Joshua Van Tol -- josh at spiny.com