BOV/BPV - Vacuum Line Question

If I'm not mistaken from your pic you are pulling source from the wastegate for the BOV? If so, neither are getting enough Vac. They should both have their own Vac source IMO. The best place to pull your BOV's source from is the brake booster line like in Zoom's photo/diagram. There is more than sufficent Vac in that line to pull the BOV open while accelerating. Another reason it's such a great source is that (for most drivers) it isn't being used when the BOV is. In other words not many people are engaging their brakes at the same time they are rapidly accelerating through the gears. It's up to you how you want to set yours up, but if you want to get that nice GReddy whistle I would say you need to move your Vac source to the brake booster line.
 
vodapas77 said:
...but if you want to get that nice GReddy whistle I would say you need to move your Vac source to the brake booster line.

I agree... If that still isn't enough sound for you then get a vented hood.:)
 
505zoom said:
I agree... If that still isn't enough sound for you then get a vented hood.:)


The hose that is circled in my picture is where i spiced in for vacuum. It did not go to the wastegate it is used by some sensors (not exactly sure what). Several people have confimed that it is for sure a vacuum line.
 
celdridge said:
The hose that is circled in my picture is where i spiced in for vacuum. It did not go to the wastegate it is used by some sensors (not exactly sure what). Several people have confimed that it is for sure a vacuum line.

I see how you have it hooked up, and I can tell you that the brake booster line will give you positive results if you hook both of your BOV's to it and give the wastegate a clean untapped source from the manifold.
 
505zoom said:
I see how you have it hooked up, and I can tell you that the brake booster line will give you positive results if you hook both of your BOV's to it and give the wastegate a clean untapped source from the manifold.


Ok ... i will try that tomorrow ... i just freakin hate cutting that brake booster line to tap it. What size connectors do i need for it? Would i be better off just buying a vacuum rail?
 
celdridge said:
Ok ... i will try that tomorrow ... i just freakin hate cutting that brake booster line to tap it. What size connectors do i need for it? Would i be better off just buying a vacuum rail?


BTW ... there are 2 hoses back there that look exactly the same ... how do i tell which is the brake booster line?
 
Okay, use the diagram I posted on the other page and this pic:

vacuum%20booster.jpg


The orange arrow is a good place to orient yourself with the proper line.

I will dig up the vac T assortment part number for you...
 
505zoom said:
Okay, use the diagram I posted on the other page and this pic:

vacuum%20booster.jpg


The orange arrow is a good place to orient yourself with the proper line.

I will dig up the vac T assortment part number for you...


Ok ... so it is the line that comes from the firewall then ?
 
This pic is from mazdaspeed75...

Get two of these from autozone. Each package comes with one of the T's that you need.
 

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celdridge said:
Ok ... so it is the line that comes from the firewall then ?

Yes, that line with the silver clamp and orange arrow pointing at it is the one you want. There is a fitting inside the brake booster line that you need to feel around for and avoid... it will feel like a hard lump in the middle of the line. Put your T's on the passenger side of that lump.
 
505zoom said:
Yes, that line with the silver clamp and orange arrow pointing at it is the one you want. There is a fitting inside the brake booster line that you need to feel around for and avoid... it will feel like a hard lump in the middle of the line. Put your T's on the passenger side of that lump.


What is the lump ?
 
celdridge said:
What is the lump ?

I believe that it is some sort of regulator to keep the brake booster from seeing any boost. Not 100% on that though, someone correct me if I am wrong.
 
505zoom said:
I believe that it is some sort of regulator to keep the brake booster from seeing any boost. Not 100% on that though, someone correct me if I am wrong.


OK ... its all done ... the wastegate now has its own vacuum source and i tapped the brake booster line for the BOV and the BPV. The greddy is a little louder now ... but nothing compared to what i think it should be. Its all whistle and no PSSSSSST.

Any ideas?

Pics if you want them:
 

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