I just put my kit on and it is working fine. No stalling or stumbling whatsoever. THe thing is taht when u are on boost and let of the throttle slightly, u also get the BOV whistle. I know some people have it flutter when at partial boost. I have 6-7 threads above the locking nut.

My question is how many threads are on your adjustment screw? Also, what kind of sound are you getting when letting of at partial boost (flutter or whistle)?

 

I usually get a little of both, depending on how much boost. If it is driving around my neighborhood, I'll get a whistle, but if it is on the highway and I don't totaly let off the gas I get a little flutter. I don't rember where I have it set right now, maybe about three or four turns after resistance from the spring.

 

How many threads above the nut? BTW, Im running VTA. One interesting thing I felt was that it spooled much better and stronger when the boost came in, but it felt weaker at the top end compared with the stock BOV. DO I need to adjust the Greddy tighter?

 

It sounds like you have it pretty tight already. Mine ran like **** when I had it vta, but try this. back the adjustment screw allthe way out until there is no pressure on the spring, then tighten it slowly til you feel the spring pressure. Tighten it about 2turns after that. See how that works for you

 

Hey I have a greddy Type-S....I have mine turned between 1 and 2 times from the point at which the adjusting screw made contact with the spring. This seems to be working fairly well. No compressor surge....I think the valve is starting to open around 11 hg vacuum..that's when i get the whistle.

I had a seperate question as well. I know I am not getting compressor surge...it seems nearly impossible that I could be. Sometime when I shift about halfway through the powerband the car revs alittle higher.....i was wondering if it was possible that my clutch wasn;t completely disengaging when i was shifting right when the car was hitting its boost peak...thus making the engine rev a little. When i let of the gas as any speed without push the gas everything work the way it should...no speeding up..or weird pressure readings...any ideas?

 

Sounds like your shift timing is a little off to me, like you push the clutch in slightly before your off the throttle... Just my opinion, not dissing your driving skills.

 

Nah its cool...I was thinking that too.....its just that I never really noticed it before. Maybe I just started listening because of the BOV....I guess I did start noticing it after I installed it. Is there a possibility that the clutch is wearing out and has actually moved the clutch engagment point that would actually throw off what I was used too? I'm a pretty good driver...I do racing schools and autocross and stuff. I never rule out the driver as a factor....is just seems weird in this case...i;ve been driving manuals for a long time. I'm semi baffled I guess

 

I haven't had any drivability problems, but it's tough to tell sound wise with my setup. I've got a HKS intake pipe, but a stock intake box. So when the turbo spools you can hear it pretty loudly. When you let off boost completely, it will "chirp" and it sounds like a puny VTA BOV. Currently, I have it at around 1.5-2 turns from where it meets the spring (one spring mod). If I tighten it more, like 3-4 turns, I get more part throttle bucking (similar feel to stock) and the BOV doesn't chirp when I let off boost. Either way, it appears to be holding the same amount of boost on WOT... what exactly should I be trying to listen for when it flutters?

 

not sure...mine never fluttered.....it was either to tight and got compressor surge......i couldn't seems to get it to flutter.....just trying to figure out my revving thing.

 

Its a lot easier for me to just count the number of threads and then go from there than what everyone is saying to turn it till it pushes against something and then go a few more turn more. So can someone count the number of threads above the locking nut?

 

hmmm i always thought the whistle was normal... i had it on my last car and my buddy with a gst has it as well (both setups w/ the type S)

 

The whistle is normal. I thought it was referred to as "the Greddy whistle"?

 

the whistle is normal.......anyways an update on my compressor surge problem. I have concluded that it is compressor surge that is causing my car to over rev....I took off the greddy type-S valve and reinstalled the stock valve. I am still getting compressor surge....everything on the car is stock as far as the engine goes right now.....what else could be causing the surge? it only happens between like 4-5.5k rpm letting off quickly...or between shifts. Its like the valve isn;t getting open all the way or something. I took the valve apart checked everything....even tested the valve for a vacuum leak...nothing. Its something with the car...any ideas? Thanks!

 

bump

 

Hm, I was under the impression that the whistle was a result of having the screw too tight. Has everyone here done the one spring mod already?