The bottom picture is NOT correct. Since the same line is used for the changeover vacuum, you MUST use the check valve to control flow to that.

 

Yes, that plumbing is the same as mine and it seems that it is wrong...but Im not so sure.
If I'm understanding this right, the check valve is in the wrong place. That setup has the check valve inline with the BOV and the changeover valve, I think what 1999 is saying it should only be inline with the changeover valve and not the BOV, which makes alot of sense to me. This however makes VF engineering installation pics wrong.

 

How you explained it is EXACTLY correct. However, also REVERSE the check valve so the BLACK side is on the intake side. This will hold vacuum that is necessary for the changeover valve.

 

1999 email the photo, I will host it up! Jimenezf@optonline.net

 

You must be special you can post up pictures. I spoke with Todd at EVO somes years ago and I think they used to have it set up that way (1999) but changed for some reason to the way we have it now, I could be wrong here.

 

Im sure there's alot of this setup out there, and its these little detail that will always bite you in the *** in the end...

 

Thanks 1999, yeah that setup is more like it. I hope people will take note. Again, thanks

 

No problem.

 

Hey Todd@evo, Sharkster, or anyone, can you verify between the two setup, post #37 seems to be the right install rather than VF install pics at post #31. TIA.

 

From your picture Mother, looks like you have check valve inline and yours will not work properly either.

 

I'm Irish, therefore, I am always right.

Let us know how the new found power feels.

 

What does this changeover valve do? Anyone.

 

I'll take it off the lift and work on it tomorrow. I should do a before and after drive, just to see if were talking big differences. Maybe thats why it goes unnoticed, the diff is small. But I paid for full boost! Thanks again.

I worked in tallaught for about a year (new cadbury gum factory installation)... you Irish's are fiesty people!!

 

It controls vario ram, I believe.

 

In a N/A engine, there is some benefit to creating turbulance in the intsake air at specific points in the power curve. The way Porsche does it is to make the intake length shorter and longer at different times. There is a butterfly (resonance) valve in the middle of the back crossover intake tube that is opened and closed based on vacuum controlled by the changeover valve. The butterfly is open with no vacuum.

When closed, the intake is short and when open, the intake is long. The length of the intake effects the torque of the engine, much like a higher manifold did with the old carb systems. When the intake is short (valve closed) and then opens up, it creates a turbulance in the intake air and allows for more forceful (ram air efect) mixture of fuel into the engine. This is the KICK people feel when hitting 5100 rpm at WOT.

The valve works as follows:


Switchong points of Resonance Valve:

Not actuated from 700 to 3120 rpm and from 5120 rpm .

Actuated from 3120 to 5120 rpm , if the throttle is also more than 30 % open at the same time.