And For Today’s Installment of NAME THAT SOUND…
02-23-2014, 09:08 AM
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And For Today’s Installment of NAME THAT SOUND… I have a Tial 50mm BOV located on the charge pipe just above the intercooler. I also have a Bosch BOV just after the outlet of the supercharger. I was not pleased with when the Tial was opening and decided to change the spring. I went from the plain non-painted spring to the white spring (from 11 to 9 psi spring pressure).
The valve now operates as it should. BUT I am getting this odd popping noise when the valve is fully open. Is this normal? It only occurs when the valve is open and immediately goes away as soon as I bring up the manifold pressure to close the valve.
I never had this noise when the Tial would open with the 11 psi spring but I have changed a couple things with the intake pipe along with changing the spring. I moved my IAT sensor and meth nozzles as well as got rid of my MAF. I can’t imagine any of those changes would cause such a noise.
I have verified the noise is definitely coming from the intake pipe. I am not referring to the popping sound coming from the exhaust.
So, any idea what this sound is?
Jayson
The valve now operates as it should. BUT I am getting this odd popping noise when the valve is fully open. Is this normal? It only occurs when the valve is open and immediately goes away as soon as I bring up the manifold pressure to close the valve.
I never had this noise when the Tial would open with the 11 psi spring but I have changed a couple things with the intake pipe along with changing the spring. I moved my IAT sensor and meth nozzles as well as got rid of my MAF. I can’t imagine any of those changes would cause such a noise.
I have verified the noise is definitely coming from the intake pipe. I am not referring to the popping sound coming from the exhaust.
So, any idea what this sound is?
Jayson
02-23-2014, 10:11 PM
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Sounds to me like the BOV is trying to close while boost is still being bled off.
A supercharger set up should run like a 5psi spring. The lightest spring pressured offered for your particular BOV.
Your BOV should be fully open at idle on a blower car. As soon as you tip the throttle, the valve should start closing, be fully closed at zero lbs of vacuum. Then open immediately with ANY vacuum. Have you confirmed this is the way it operates on your car?
If you have to stiff of a spring, the boost will actually push the valve open instead of the vacuum pulling it open. Then try to close prematurely. Defeating the purpose of the BOV.
A supercharger set up should run like a 5psi spring. The lightest spring pressured offered for your particular BOV.
Your BOV should be fully open at idle on a blower car. As soon as you tip the throttle, the valve should start closing, be fully closed at zero lbs of vacuum. Then open immediately with ANY vacuum. Have you confirmed this is the way it operates on your car?
If you have to stiff of a spring, the boost will actually push the valve open instead of the vacuum pulling it open. Then try to close prematurely. Defeating the purpose of the BOV.
02-24-2014, 03:52 AM
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As above, sounds like air trying to back up and go back out through the blower because the BOV isnt venting properly.
The BOV must be open at idle and cruise with a supercharger.
The BOV must be open at idle and cruise with a supercharger.
02-24-2014, 08:10 AM
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My first thought was flutter too but I just had never heard BOV flutter like this before.
There are two lighter springs available; 7 and 3 psi spring pressure. I am concerned that the green (3 psi spring pressure) spring is too light. I would prefer the car not sound like a street sweeper all the time. Since this BOV was installed by a previous owner for primarily sound and is a secondary BOV I was hoping to tame it a bit and not have it open all the time.
The BOV is operating just as I would like/expect it to with the new white spring. It now opens at idle, deceleration, and during shifts, unlike my previous spring. The only concern is the popping (flutter) sound.
I was going back and forth over getting the white or black spring (-9 psi spring pressure vs -7). Seems like I may have picked the wrong one…
There are two lighter springs available; 7 and 3 psi spring pressure. I am concerned that the green (3 psi spring pressure) spring is too light. I would prefer the car not sound like a street sweeper all the time. Since this BOV was installed by a previous owner for primarily sound and is a secondary BOV I was hoping to tame it a bit and not have it open all the time.
The BOV is operating just as I would like/expect it to with the new white spring. It now opens at idle, deceleration, and during shifts, unlike my previous spring. The only concern is the popping (flutter) sound.
I was going back and forth over getting the white or black spring (-9 psi spring pressure vs -7). Seems like I may have picked the wrong one…
02-24-2014, 04:49 PM
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How much boost are you running? Tials are know to have the flutter sound under certain situations. If it is in fact fighting boost pressure to close, this would cause the flutter noise.
It's a supercharger, their loud. The only way to kind of get away from the blowing air sound at cruise is to recirculate the air back to the inlet hat. You will loose your BOV sound though. Can't have one with out the other, and it not have an ill effect on your blower. A blower not being able to vent properly is worse than a turbo not venting properly.
It's a supercharger, their loud. The only way to kind of get away from the blowing air sound at cruise is to recirculate the air back to the inlet hat. You will loose your BOV sound though. Can't have one with out the other, and it not have an ill effect on your blower. A blower not being able to vent properly is worse than a turbo not venting properly.
02-24-2014, 05:24 PM
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12 psi
I like the air sound coming from the BOV but I don't like the sound of marbles in my intake. On another forum a member said he had the same thing and what solved it for him was moving the BOV further away from the throttle body (about 8 inches). Not sure what that means. Pressure wave from throttle body? No idea...
I like the air sound coming from the BOV but I don't like the sound of marbles in my intake. On another forum a member said he had the same thing and what solved it for him was moving the BOV further away from the throttle body (about 8 inches). Not sure what that means. Pressure wave from throttle body? No idea...