I just kon't know enough about the BOV to tell you about the vacuum hose, but I am going to install the billit aluminum BOV that Evo sells. I have posted many pictures on this forum, just search under my Wyo996, sorry I am so computer illiterate to whip out a picture. Will

 

will do... thanks

 

There any number of ways of doing this, the course in-line fuel filter method:

http://www.webbspot.com/porsche/html/crank_vent.html

or finer filters that drain back to the crank. Location depends on where you have the room, I feel comfortable when I can visually inspect it and easliy service it. There are some good threads either here on this board or rennlist, run a search on catch can etc and see what you come up with.

 

what picture is it that you want to show? I have the billet BOV, thought they (EVO) prefer to call it a recirc valve. When the throttle is close, vacuum is present after the throttle, therefore the recirc valve is open so that the charge air has somewhere to go (back to the intake).
But my problem is, if there is vacuum present already when the engine is off, how does the vacuum clear to get maximum boost. IS there a purge vent or something at the valve itself, or do you get rid of the inline check valve to get rid of the vauum?

 

Give us a picture of the line coming from the valve and exactly what it goes into. You are correct that the valve it not to have any vacuum at WOT.

 

the check valve is stock, vacuum is present at the white side of the valve and gets trapped, the black side prevents the vacuum to flow back to the throttle side. How does the vaccum release?

 

Looking at the picture, seems like BEFORE the vacuum line from the valve gets to the check valve, it splits off to the electrionic changeover valve for the resonnace valve on the intake tube. I do not see how this setup can release vacuum,, as you questioned. The check valve is not going to allow any vacuum to escape and the changeover switch is not going to either, which, as you stated, will cause the bypass valve to always remain open.

The only way I can see the setup working properly is if the line heading towards the changeover bleeds to the atmosphere which would not be proper either as it would create a vacuum leak unless it's programming control has been altered.

Please verify for me where the hose off the tee goes to and if it is the changeover valve, does it connect to the straight nipple or the one on the side?

There is probably something I am not seeing becuase if the valve was NOT closed at boost, not only would you notice the power loss, but it would also cause the air movement to be much louder than normal.

 

1999,
Please verify for me where the hose off the tee goes to and if it is the changeover valve, does it connect to the straight nipple or the one on the side?

The straight nipple you refer to? are you talking about that thin metal tube, maybe 5"-6" long as shown in the pics. Where is the changeover valve located?

Also, if you look closely at the tee and the check valve, I put tie wraps on there cause I thought the hose was a loose fit. Do you think they have this in mind as far as venting the vacuum? Seems cheesy if they did.

You bring out a good point about the reprogramming the changeover valve. I pulled out the hose while engine is off and vacuum was present. I should put an inline gauge if there is vacuum present when at idle. Any recommendation on this one?
Im def creating boost and pulls strong, but might not have a good reference in relation to before.

The weird part is, this vacuum setup is exatcly how its done on there installation cd that came with the kit. So theres gotta be some idea behind this.

The only way really is to get rid of that check valve...this will vent the vacuum back to the throttl side.
Is there anyone else with this setup? I guess all of us should...except for those hardcore, who like to fiddle people.

 

HA! If I ain't breakin' it ... I ain't haven FUN!!!

 

1999 is the changeover valve a 3-way? does it release it this way? Just another possiblity to release vacuum. In reality, in stock form the check valve is there and its straight to the changoever so it has to release from there, correct?

 

The changover valve is located just behind the top of the alternator and has 2 vaccum lines going to it. Typically gray in color, this controls the opeing and closing of the resonance valve on the back crossover intake tube. Like a Turbo, your boosted engine does not need this valve to close at all. However, the changeover valve must remain operating otherwise you will throw an CEL.

Forgetting the tee for a minute, the line from the bypass valve to the check valve will never allow the valve to close. Now we have the tee and need to know what that line is connected to and how air is released from it.

A fast and simply way to test if you are getting boost, without a gauge, is simply to disconnect the vacuum line from the bypass valve and plug the hose. Take the car for a run and if the valve had been open before, you will know it.

I see no reference to that check valve in my install instructions. Can you paste and copy the part that references this?

Otherwise, the proper way to test it is to remove the hose from the bypass valve and plug in a vacuum gauge using a long enough hose to get it to your driver's seat. Take the car for a spin and you should lose all vacuum at any speed at WOT.

 

I would rathere have fun when I have full boost!!

 

Well, for some reason 6peed is not allowing uploads right now. It is as I suspected...your current setup will not work properly. The hose from the bypass valve is to be connected directly to the intake. That hose is to be cut a few inches away from the intake and install the tee. To that tee is a short hose, then the check valve (FLOW TOWARDS INTAKE) then hose to resonance valve. That will work fine. i.e., the bypass vave's vacuum sourse is uninterrupted to the intake.

Send me your email and I'll forward the pic to you.

Jim


BTW: Who did the install?

 

however at first, they took the check valve out and just the tee was connected.

Then when I saw that image from evoms, I installed the check valve myself, cause in reality without the S/C and in stock form how will vacuum vent anyway after the checkvalve. The setup didnt change. The only thing that changed was the added recirc valve.

So I guess I'm taking off the check valve and the installation pics is wrong?

By the way... Jimenezf@optonline.net

 

Is this what you have regarding plumbing?

http://www.webbspot.com/porsche/html...ter_valve.html