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Discussion Starter #1
hey guys...
got the AA bpv in, but honestly dont feel a diference when moving the adjustment screw...
anyone knows how to adjust these..???
regards
jorge saca
 

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I think it has been pre adjusted by AA experts, so i didn't make any adjustment when i installed my c38 kit.

What kind of difference are you looking for when adjusting?
 

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Discussion Starter #3
well the purpose of it is to be able to adjust when it opens and closes, because if it is opening to soon, you are loosing boost.
regards
jorge saca
 

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I tuned mine so it was tight enough to hold boost to redline.
 

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Well, a boost gauge is critical. Even better would be some logging software so you can more closely analyze the boost levels at various RPMs and how the boost levels react to throttle position. However I didn't do any logging.

I simply backed off the spring tension completely so it wouldn't hold boost. Then I tightened the spring just enough to hold boost to redline and then tweaked the spring tension until I liked the way the throttle response felt in that transitional throttle zone between vacuum and boost. That way I'm not into boost while under most part throttle highway cruise conditions which should reduce fuel consumption and personally I fee it improves the smoothness of the throttle response.

I'd be very interested to hear from AA if there are any caveats to tuning the BPV.
 

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Discussion Starter #7
thanks for your reply guys....
travis, you have vacuum going into your top part (black part) right??? and no vacuum on the lower part right....
so when you are at 10 psi for example, there is also 10 psi going into the top of your valve through the vac line...
this helps you keep the spring down.
my question is, how would you know when the adjustment screw is tight just enough to hold boost at redline????
thanks
jorge saca
 

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<snip>
my question is, how would you know when the adjustment screw is tight just enough to hold boost at redline????
thanks
jorge saca
It doesn't need to be exact. You just don't want it so loose that you lose boost. I guess it's more of a situation that you want to make sure you're not leaking boost when you've found a sweet spot.

However, like I said, I'm speaking from my own limited experience. I'd love to hear from "the experts".
 

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I would follow AA's instructions and advice on where they tell you to set it, then slightly tweak it from there.
 

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I would follow AA's instructions and advice on where they tell you to set it, then slightly tweak it from there.
I received no instructions regarding BPV adjustment with my kit, at least not that I can recall. Do you have the instructions?
 

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Discussion Starter #12
does playing with that adjustment screw really make a difference???
ive tried all open, and all closed, and seems to be the same.
regards
jorge saca
 

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does playing with that adjustment screw really make a difference???
ive tried all open, and all closed, and seems to be the same.
regards
jorge saca
Definetely makes a difference!

Just call AA tomorrow while your under your hood, they will walk you through it, it only takes 5 minutes.
 

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It makes a difference. Mine won't hold boost if it's fully open. Aside from that I think it's a matter of personal taste.
 

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Discussion Starter #15
ill give it a try again once i put my engine back together....
as for now, i am happy, as i think i finally discovered my boost leak.
i think i have a cracked intake manifold....
ill put the new one in today, and try it....
regards
jorge saca
 

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Yesterday i tried to adjust the BPV, but i really didn't feel any big difference. Logging might help, but tuning with just boost/vac gauge is hard. It held boost (boost gauge showed) when it was fully open and when it was closed.
 

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Discussion Starter #17
i tried streching the spring a bit yesterday, and i also removed the inner nut on the adjustmens screw to be able to close it even more downwards...
i did that, and my VAC improved a bit, and i think i got a little bit more boost...
maybe a 0.8 psi or so..
regards
jorge saca
 

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Craig from AA told me: "The Blow off valve is usuall adjusted by screwing out the bolt, then turning it back down till you feel resistance then add 4 more turns and lock."
 
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