intake prrs like a cat?!
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intake prrs like a cat?!
So about a week ago I installed a freshly rebuild td04-19t. I took the car out for a ride and everytime I went into full boost and I would let the gas pedal off the bov would go off and the intake made a weird sound. It kinda sounds like the air is not fully coming out of the bov. I adjusted the spring on it and it's still the same. I have a Greddy type rs bov, 3" intake elbow to behind the headlight with a k&n filter. My guess is that the bov is not letting the pressure out of the IC causing the air to hit the turbo? What do you guys think?
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no i didn't take it out. I just replaced the turbo....and how could i hook it up backwards? at low and high boost it seems to be good, its mostly at middle boost....i dont know if its surge tho cause it kinda sounds like the bov but a deeper noise
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http://www.youtube.com/watch?v=kfw_mTEVFuM
it sounds just like this clip....its a greddy type rs too....i wonder if its a problem with these bov or if its supposed to sound like that. only thing is my car never sounded like this before the new turbo
it sounds just like this clip....its a greddy type rs too....i wonder if its a problem with these bov or if its supposed to sound like that. only thing is my car never sounded like this before the new turbo
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I've heard plenty of other cars with part throttle lift compressor surge just like the one in the video.
I'm going to speculate that the BOV mechanism is not moving freely enough to be operated by the supplied vacuum. If that is so, clean/lubricate the valve assembly, reduce spring tension more if possible, and/or attempt to determine if your plenum vacuum is leaking somewhere. This part is guesswork for me.
What I do know is that your larger compressor wheel has a different map and your surge line has stepped to the right on the chart. This means at part throttle you might have surge as a frequent dinner guest now. And fiddling with the BOV may garner zero gain.
I will defer to those with more edjumuckayshun in the subject to support or supplant my theories.
I'm going to speculate that the BOV mechanism is not moving freely enough to be operated by the supplied vacuum. If that is so, clean/lubricate the valve assembly, reduce spring tension more if possible, and/or attempt to determine if your plenum vacuum is leaking somewhere. This part is guesswork for me.
What I do know is that your larger compressor wheel has a different map and your surge line has stepped to the right on the chart. This means at part throttle you might have surge as a frequent dinner guest now. And fiddling with the BOV may garner zero gain.
I will defer to those with more edjumuckayshun in the subject to support or supplant my theories.
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