in this diagram :



there is a yellow Vacuum line that goes from the turbo y pipe ... to the Lower Intake Manifold .. that feeds some air to the primary injectors ...

what`s the deal with this hose .. it is necessary.... isn't this really a vacuum leak
would it make a huge different in fuel atomization if it`s capped off ?

thx

 

Its not a vacuum leak. It supposedly feeds air to help atomize the fuel.

 

Do not cap this. It's there for a reason. Any source of air before the throttle plates will work.

 

on the OEM setup it is fed to a nipple which also sees positive pressure
and on the diagram ^ ... it says atmosphere ... should i... or have any of you ever left the hose with a filter ( from the rat nest solenoids ) vented to atmosphere ... ?


im really out of things to twiner with on my car lol

 

sorry, it says atmosphere because that diagram is from a series 3 GSL-SE naturally aspirated engine (notice the top feed injectors). Boost pressure (and atmospheric depending on engine load) is fine. That's how the 2nd gen turbos did it--the atomization ports were fed by a port on the UIM that pulled air from before the throttle plates. in fact, the series 5 had 3 atomization ports, one for the primaries and two separate ones for the secondaries. all were fed by the UIM.

 

I've seen some cars idle smoother with this left intact or replicated on a modified setup. On others it doesn't seem to matter much.

 

i really appreciate all your inputs .. thx a bunch guys

 

were can i find this diagram for a single turbo setup on an fc??? caus i pulled my motor a few days agio to rebuild it and the vacuum lines like nuts under the intake manifold ima need help aka diagram to put it back together lmao

 

in the FC forum?