BOV and Vaccum Lines

[jeffball610]

I've been searching through posts to try and find decent info. Being these forums are so old, it's tough to find things. I've decided to install an upper intercooler pipe and BOV to extend the life of my components until I get my engine swap further along. I found one thread which describes a BOV (I already knew that info), and another that describes where the stock vacuum lines go.

However, I'm not finding info on how to hook up the vacuum port on the BOV. I know it needs to come after the throttle body plate, but which one is best?

After I get that installed, I know I'll need to reset my idle (it sucks now anyway) and there was a decent thread on that. 

 

[kev]

couple options:

1. Could tap into the rear most vacuum port on the TB (the one closest to the firewall in the set of three).  Although, I've had issues with getting enough volume to properly operate a BOV.  

2. Could tap into the vacuum line going to the brake booster.   Many delete their OEM rear ABS.   If you replace the factory 'T' that used to go to the ABS with a normal T, it is the perfect spot for a BOV vacuum.   I've also used the factory ABS 'T' but drilled out the check valve inside it on the abs wing.    

3. There is a plug on the intake manifold on the runner to cylinder 4 (on manual cars). [It may actually be right in the middle of the Y for runners 3 & 4..I can't remember exactly.  But if you can't find it, I can snap a photo of it on my car later on]  This is a perfect spot to remove the plug and install a nipple for the BOV.  If your car is an automatic, there is a nipple there already that goes to the trans.  Just T that line. 

Basically, you need to get vacuum/boost from after the throttle plate.   The only factory vacuum locations are what I described above.  

Kevin

[jeffball610]

I got everything welded up and installed this weekend. Seems to function normally. However, I still need to fix the idle and the throttle stop. The throttle sticks open just a bit causing high idle and obviously won't let the BOV do its woosh thing as easily.

I did T into the brake booster line just to get the largest source possible as suggested. What is the facotry source below the throttle body for? It goes to the stock tube over the valve cover, almost as if it was meant for a BOV.