I removed the stock BOV yesterday and I noticed this extra passage which goes all the way up to the top of the BOV. I tried sucking and blowing through it but is seems sealed, at least as long as the BOV is shut. I was not able to test the same with the BOV pushed open. The paperclip I sticked in there would not move either when I pushed the BOV open so it appears it might be going back to the sealed portion of the vac side.
Any idea what this passage is good for? Maybe it is to help keeping the BOV shut at high boost? The spring tension is pretty high... wouldn't make you think it's necessary.
Any idea what this passage is good for? Maybe it is to help keeping the BOV shut at high boost? The spring tension is pretty high... wouldn't make you think it's necessary.