i installed my aps cai, and got a tinch of compressor surge sound... so i opted to tear apart my worx bov last night and reset the spring, thinking that i perhaps alwayse had a little, but was unable to hear it. now on the lowest spring setting i'm still getting a shoop ahoop sound. in addition to a harsh/hallow plastic krachu in shift events... almost sounds like an apexi BOV.. this sound is originating from the passanger side. expecially in that noisey prespool state. i'm going to put the stocker bpv back on this evening to see what happens, but my question to you.... #1 do you get shoop shoop sounds? #2 the hollow plastic sound happens on full bypass or full recirculate, what is the cause of this?? stock turbo inlet?? thanks
Well without being there to hear it it is hard to say. So let me describe a situation to you and you tell me what it does. You driving along at a cruise in 6th gear and you give it a little throttle to pass a car. Does it make a pssh pssh pssh sound with it tapering down to nothing? But then you are going along in 6th gear and you give it 100% throttle and you get nothing? M
yes a little throttle and a little boost will give a little shoop shoop noise when i lift off the gas. if im at wot and let off i get a kerrrshu sound with no shoop shoop... and this wot sound is very plastic sounding, like there is a little dude under the hood punching an empty milk jug. maybe i should record it.
OK that helps a little: Compressor surge is the turbo spooling at light loads and it blows open the BOV and is vented back to the intake pre turbo. What then happens is the turbo cavitates muck like a boat when you turn to sharp. " yes a little throttle and a little boost will give a little shoop shoop noise when i lift off the gas." 100% sure it just happens when you lift off the gas? If so you have a BOV issue, is it a 50/50 unit or 100% I think I remember you have a Forge unit correct?
it's a worx. i can set it to 100% recirc to 100% atmosphere in 4 steps.. i get the surge no matter what the setting is at. which is why i tried to clean/lube and reset the spring rate. all failed.. i will try the stock unit tonight...
It is the bypass part of the valve. Mine does the same thing. With little boost it recirculates (quick little flutters) and once you get more boost (wot) if vents to atmos and make the normal bov sounds. Of course, this is only when you LIFT off of the gas. If it happens when you are ON the gas, it is something different. Russ
From what you described here I dont think you have a problem. You say the sound is when you lift off the gas, that is when the BOV should open. I think you are just not use to the new sounds with the open CIA. Matt
i concur. i swapped in the stocker last night, and was getting the same slight shoop shoop at light throttle/boost with a lift. i was hoping that it was just me being to concerned and inexperienced with the cai noises.. thanks!
also just curious, what would an oscolating vibrato almost chatter sound at high boost/wot denote? wastegate flutter??
