So I have two blow off valves on my intercooler piping. I have been told that one is likely a pop off valve. They are both hks but one has two vacuum nipples and one has only one. Why would a blow off valve have two vacuum attachments? The one with two vacuum nipples is probably twice the size of the smaller one with only one vacuum nipple. Any ideas? I will probably remove one, just trying to figure out what the deal is with the larger one and two vacuum nipples.

 

Looks like they are actually bypass valves. I am still running stock ECU and the AFM. Do I need to vent this back into the intake and if so, where?

 

pictures would be grand

 

Im going out on a limb here, I am new to turbos, boost in general. Is it a BIG bov? Maybe if its super duper huge it needs 2 vacuum lines to assist the spring in there to open? Just a idea.

 

On my original setup the previous owner had a BOV with two nipples and they were both hooked up at the same vacuum source, after the throttle body of coarse, and it worked fine. BTW it was a old HKS BOV.