Yeah, a friend has a tial laser and his has that exact same sound ch chi chi (fluttering) ..he's know's its surging. Now that I have installed the Green and Dejon 3" intake, I can hardly hear my bov at all, but I sure can hear the turbo spool. I don't know what it is with the Dejon Intakes and BOV sound ...my stock intake was always louder with the BOV, but couldn't hear the turbo spool like the dejon.
Im getting these troubles when i back off mostly with cruze control on at around 120km/hthe car lurches forward after throttle closes i have no braeks in my bov hose but i do have standard cooler and pipes.
Wastegate is source pressure from upper ic pipe.
what problems does it cause.
Any suggestions thanks.
The reason I think I have compressor surge is because of lag between shifts at high rpm. I had the fa fa fa fa flutter before, but fixed it. Is it possible to my bov is simply not releasing enough between shifts?
I'm 99% positive that all these guys are describing blow off valve flutter, which is common with the more meaty BOVs like TiAL and HKS, and even a misadjusted Greddy .. and not compressor surge.
I'm no where near a "wiseman" so I'll start off with a criptic description and let the smart guys fill in the blank if they choose.
Compressor Surge is when compressor or turbine side (not sure which) of the turbo out does the other with regard to the air flow characteristics....... Dang, that's really bad. I'll stop there.
:: "We Need A Wiseman To Aisle 6 To Clean Up Pete's Explanation" ::
Anyway, from what I've been told compressor surge will be seen when on the gas and the engine appears to buck in the midst of acceleration(even seen a dyno video that showed this - I think)
Please, someone chime in hear and save my dwindling thought. Thanks.
^^^^
What he said. I have a HKS SSQV, and it flutters when shifting on mid to low boost, and it fully opens on full boost. I haven't heard a HKS SSQV that didn't do that. Also I've heard some TurboXS blow offs do this too.
Hehe, this thread is old, and you guys are cute. Compressor surge occurs on the compressor side of the turbo, but can happen for a number of reasons. One of the more notable reasons is the wrong compressor wheel in the wrong compressor housing. Another contributing cause is running too small of a turbine wheel, and trying to spool a large compressor wheel up too quickly. I can get much more technical, but I don't think this thread warrants it. In all seriousness, if you don't know what compressor surge is, you probably have not even come close to a level where you have to worry about it happening. A good majority of the turbos available on the market for DSM's are sized correctly so compressor surge is a very unlikely gremlin.
Maybe Im out of my leaque here but I have a question. Is there a proper term for when the BOV for what ever reason does not do its job and lets to much air get pushed back into the compressor housing causing lag between shifts? In any case, I have this problem and figure if its not the BOV that its my internal wastegate. I hve a good flowing exhaust so that should not be the problem. The strange thing is that it happens at high rpms. Or maybe thats not unusual.
#1, read Noslaser's post. he has the correct answere for what surge is. Now to answeer yor question, lag between shifts, caused by the valve not opening, IS SURGE! But this will also be accompanied by a nice harsh bucking! If you arent experiencing this, your lag is some other problem.
Compressor surge occurs on the compressor side of the turbo, but can happen for a number of reasons. One of the more notable reasons is the wrong compressor wheel in the wrong compressor housing. Another contributing cause is running too small of a turbine wheel, and trying to spool a large compressor wheel up too quickly. I can get much more technical, but I don't think this thread warrants it. In all seriousness, if you don't know what compressor surge is, you probably have not even come close to a level where you have to worry about it happening. A good majority of the turbos available on the market for DSM's are sized correctly so compressor surge is a very unlikely gremlin. 
