I've been on the hunt for a better place to pull vacume for my BOV and have not had the best luck. I was using the big nipple on the side of the IUM and that just isnt enough for my BOV to fully open so I get a bit of comp surge. I also tyred to use all 3 smaller nipples on the front and didnt get any air from them. My question is can I tap the block off plate on the side of the UIM and hook it to the top of my BOV? I need to figure this out, the sound of comp surge on my new turbo is poison to my ears!

Here i the pic-

http://i93.photobucket.com/albums/l7...eplaces004.jpg

 

I see no reason any of those should not have worked. It does not take that much vacume to pull the spring back and allow it to vent. Sounds to me your spring is way to tight. What BOV? Can you adjust the spring?

 

I am using the Turbo XS Type S BOV. It is suposed to have a very soft spring (12-15psi tops) and is not adjustable. Im not really sure why the first plan didnt work. Maby I did it wronge, Is the three/four nipples on the front of the UIM if your looking at from the front of the car. Anyway should that block off plate provide enough air pressure?

 

Is the BOV stuck? You might try lubing it or something. I used a little air tool oil on mine, but mine is a cheap piece of crap that works surprisingly well. $20 ftw, doesn't seem to leak or anything...

 

The spring is fine and all the internals are well lubed. Im just having a hard time getting the thing not to comp surge. The BOV works but after the noise there is always a bit of a surge, so I must not be getting enough vacume So are there places I havet looked yet, or should I tap my block off plate?

 

any other takers?

 

I might have had a similar issue with my BOV. Does the 'surge' happen under acceleration? Because as I understand compressor surge, it can only occur when the intake pressure is supposed to be dropping. I had it happen on acceleration. I figured that it might be because of the strong exhaust pulses, thus creating intake pulses as well, so that without a restrictor pill of some sort the BOV would chatter sometimes, making acceleration choppy and feel simply awful. I cut a piece of a small vacuum connector and put it inline. I honestly can't remember if it's still installed, but I'm 90% sure that it is. It seemed to solve my problem. If you try this, make sure you don't make the restriction too small. At first I tried using the stock restrictor pill before both the BOV and boost sensor, but the BOV would open very slowly (NOT GOOD, I figure that's an easy way to induce compressor surge), obviously because the hole was so small.

 

No it only surges on decell. When I let off in -vacume its all surge, but when I let off in boost its the bov sound followed by the surge.

 

I have the same problem and I used the same BOV. I found vacuum signal to open the BOV on the nipple located underside the block off plate. But I can gett boost from there. The problem with this is that I dont found a good source to get boost and vacuum signals on the intake manifold. Right know I connected the boost gauge and the BOV on the same nipple, but I get only vacuum and no boost. I tried all the nipples around the intake manifold, including the one for the fuel press regulator and I dont found one that have boost/vacuum signal. I also change the boost gauge for another one, and same problems. For the moment I really dont know how to resolve this problem too.

 

I hear ya man, I'm going to try a few on the back to see if that works. If not I think I'm **** outa luck.

 

I tapped my ACV blockoff plate. Use a 1/8NPT tap, then a 1/8 NPT barbed fitting with teflon tape. But be careful about boost leaks, from both the fitting you just installed and from the upper left corner of the blockoff plate which is leak prone.

 

The right answer, get a real tried and true BOV. The vacume source is not rocket science.