Blow of valves??
#2
You don't want to do that. Because our air is metered when it enters before the BOV, venting it out will cause the car to run rich for a moment while it's open. If you wanted to get it to vent just unhook it from the jpipe and plug up the hole where it was.
If you're doing it "for the sound"... well that's just dumb.
If you're doing it "for the sound"... well that's just dumb.
#4
upgrading to a better CBV (compressor bypass valve as its known in our cars) aka BOV isn't a bad idea, but it's definately low on the priority list when you're doing mods, unless yours is broken, then you might as well buy a better one.
#5
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If I'm not mistaken...
If you upgrade to a MAP sensor with a piggy back of some sort, you aren't required to run the BOV back into the intake.
On the other hand, I run a MAF with a stock CBV. It's so loud I'd swear it has some fancy big BOV on it. (too loud for this old guy, give me a loud exhaust!). If I chage it will be to the same type but better quality CBV. The 993 valve just doesn't last.
:Soapbox Time: Check your CBV! It's probably bad... :down from Soapbox:
If you upgrade to a MAP sensor with a piggy back of some sort, you aren't required to run the BOV back into the intake.
On the other hand, I run a MAF with a stock CBV. It's so loud I'd swear it has some fancy big BOV on it. (too loud for this old guy, give me a loud exhaust!). If I chage it will be to the same type but better quality CBV. The 993 valve just doesn't last.
:Soapbox Time: Check your CBV! It's probably bad... :down from Soapbox:
#7
Race Director
Your car runs rich for a moment when its open anyway, plumbed in or not. I am about to make a new intake and plan on plumbing it back in on an angle towards the turbo inlet (am using MAP based stand alone).
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#10
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I don’t believe that the AFR is affected by where the CBV/BOV vents. It is only supposed to be open, when there is a large pressure difference across the throttle plate, which occurs when letting off the throttle after some power has been applied (gear-change, etc.). To the best of my knowledge the injectors are cut-off at fully closed throttle and above a certain rpm, so in that case, it is only breathing air anyway.
Laust
Laust
#11
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Originally posted by Laust Pedersen
I don’t believe that the AFR is affected by where the CBV/BOV vents. It is only supposed to be open, when there is a large pressure difference across the throttle plate, which occurs when letting off the throttle after some power has been applied (gear-change, etc.). To the best of my knowledge the injectors are cut-off at fully closed throttle and above a certain rpm, so in that case, it is only breathing air anyway.
Laust
I don’t believe that the AFR is affected by where the CBV/BOV vents. It is only supposed to be open, when there is a large pressure difference across the throttle plate, which occurs when letting off the throttle after some power has been applied (gear-change, etc.). To the best of my knowledge the injectors are cut-off at fully closed throttle and above a certain rpm, so in that case, it is only breathing air anyway.
Laust
I always thought I was running rich in between shift's.
#14
Race Director
Of course its ok. Its just a matter of preference for the sound. Some say that the valve returning into the itake helps keep the turbo spinning, I am not sure how much effect this has though, nor sure how you can measure it... just a physics thing I imagine.