blow off valve noise at part throttle
#1
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blow off valve noise at part throttle
I have been running a Greddy turbo kit for about two weeks now. At WOT, I build to 7psi and my bov dumps as it should when I let off. When I accelerate at part throttle and boost is slowly building, I hear my bov hissing like crazy. It will do this from just under neutral pressure until i hit about 3psi. I have been tightening the spring on the blow off valve but no change yet. I was going to tighten it more but I keep reading other post where people are having to run their Greddy RS bov's at the softest position or even cut the spring. Before I tighten it any more, I need to ask this: Is my bov suppose to vent at part throttle?
#3
The action of the blow off valve is directly related to the manifold pressure. As long as you are driving at partial throttle it will be releasing. The BOV will stay closed with boost until the spring pressure is exceeded.
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Originally Posted by Sideways,Jul 4 2010, 02:41 PM
The action of the blow off valve is directly related to the manifold pressure. As long as you are driving at partial throttle it will be releasing. The BOV will stay closed with boost until the spring pressure is exceeded.
#5
Depending on if you are seeing boost or not. Watch your Vacuum/boost gauge and see it syncs up with the BOV actions you are seeing.
Just think, if it didn't Psssssst when you give it part throttle it would take off on you building power and be very difficult to control to drive.
I can see 100 mph without boost by using partial throttle and letting the bov release the boost.
Just think, if it didn't Psssssst when you give it part throttle it would take off on you building power and be very difficult to control to drive.
I can see 100 mph without boost by using partial throttle and letting the bov release the boost.
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yes if not at full throttle or even heavy throttle, the pressure of the low amount of vac in the hose to the bov will be less than the pressure exerted on the valve of the bov and therefore it will leak through. its totally normal and is functioning correctly.
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I have the Greddy turbo kit and rs bov as well.
I have the same thing happening. I know the sound is annoying, but your going to have to deal with it. Its normal.
I have the same thing happening. I know the sound is annoying, but your going to have to deal with it. Its normal.