compressor surge

[Mr.s13r]

So why is it like this? I mean it does blow off but near the end i would hear it fluttered.

Turn your volume up to hear my car talk to ya (http://tinypic.com/r/2nsc6eg/5)

how would i got about fixing it? My hks is not the old adjustable one and it does do this when i hit about 10lbs driving as well.

[a fuzzychnchila]

Its not adjustable? If it is adjust it to HARD... If its still doing it it might be a bad BOV. :/ try lowering the boost and see if it still happens... you dnt want to mess up your Turbo...

[lazysk8er2]

well im not sure but yout really have much compressor surg while stationary so theres nothing for the bov to do. usually u need to build up enough boost while your driving and when you let off the throttle it should give u the beloved squeel you seek

[slider2828]

I think you can change the spring.... But yeah mine flutters around then... its fine.... not a big deal 10psi is nothing on a turbo

[Mr.s13r]

I think you can change the spring.... But yeah mine flutters around then... its fine.... not a big deal 10psi is nothing on a turbo

I guess it's ok then but im gonna recirculate it i guess it will help

[Artigo]

In my experience it shouldn't be fluttering if your bov is good, but I don't know for sure so I'd try all of these things.

[VNG704]

The hks bov (or atleast the newer v2 model that I have) is known to flutter the turbo on lower boost. Mine is recirculated and it flutters. Only thing you can do is buy a different bov or somehow change to a softer spring, not harder. Which would alow more compressed air out. Meaning no more/or less flutter. Turbo flutter isn't as bad as the surge during accelleration. That type of surge will destroy turbos and motors.

[jspaeth]

HKS BOV ftl.

Everyone I know who has this has compressor surge, and I personally think the blow-off sounds terrible.

I am running a Greddy RS vented to atmosphere, no problems. Doesn't leak, the sound isn't cheesy (just a pfhhhh) and holds boost beautiful.

Doesn't chatter as much as SSQV

[g-via]

I have the Greddy RS also, at low boost it flutters, which sounds like compressor surge

[VNG704]

HKS BOV ftl.

Everyone I know who has this has compressor surge, and I personally think the blow-off sounds terrible.

I am running a Greddy RS vented to atmosphere, no problems. Doesn't leak, the sound isn't cheesy (just a pfhhhh) and holds boost beautiful.

Doesn't chatter as much as SSQV

I have the Greddy RS also, at low boost it flutters, which sounds like compressor surge
So....then they are pretty much the same.

turbo flutter is compressor surge... it just isn't the crazy turbo/motor killer kaboom surge.

[NismOkatFreaK]

I have the ssqv and it doesn't flutter at all, sounds like an air compressor when you pop a hose off with pressure in it still, just a clean burst.

[BoostSlideWayz]

Did it just start doing this ? or did u have it for awhile

[Mr.s13r]

It just start doing this. After it hits around 11 or 12lbs it would blow off then flutter

[ILoveJDM]

ssqv's flutter on high load, low rpm.

onramp+5th gear+2500rpm = full flutter

[Mosaic]

Just thought I'd jump in here as i am testing a new product which is meant to give a BOV both the benefits of a stiff and soft spring AT THE SAME TIME.

The purpose of a BOV from the factory is just ONE thing, to prevent Turbo flutter/surge and thereby reduce potential servicing requirements for borderline spec turbos. If your turbo is in good shape, well in spec, low boost flutter does not harm it although it despools it. A well used turbo will suffer at the hands of compressor surge so its NOT a GOOD thing to have in any event. It's something you tolerate, not want.

A soft spring BOV reponds passably quickly to surge but does NOT repressurise the intercooler to give u boost as u complete your gearshift. Therefore it's not the BEST for car performance, but it is for turbo longevity.

A stiff spring cannot react to surge well (opens late) but it does give you some boost before as you complete your gearshift. This happens 'cause the spring tension shuts the BOV early to generate boost in the intercooler before you clutch out.

The product being tested 'upgrades' your BOV to electronic control to deliver both fast surge response AND fast shutdown to enable boost before clutch out. Its also tunable to your application from INSIDE the cockpit AND comes with a preset for time attack with max sensitivity as opposed to the tunable preset for street driving.

This is not yet a commercial product, I will become a commercial member when it is launched. Therefore all I can say is the cost of the system is surprisingly competitive.

[lbsam]

^^ interesting..

[slider2828]

At low boost, compressor surge is not a big deal.... its actually a good thing, it keeps the system pressurized... No big deal... Mine flutters at <10 psi... 14 and 18 psi I have full blow off... I think this is probably most ideal situation....

I have run it like this for 2 years and I have 0 shaft play on my turbo and I track my car all the time....

[Options13]

i have a v2 ssqv, and it flutters when i just let off the gas when im at like 10in/hg

but when i full boost (7psi) no surge at all

[Mosaic]

U r right slider u want some pressure in your I/C, however more pressure in I/C is better. So its a balance between flutter/surge and pressure in I/C. As i said, low boost flutter will count if your turbo is worn and not if it isn't. U juts one of the guys with a good turbo. What abt all those ppl with slightly worn turbos?

[slider2828]

Turbos will go out whether if it has surge low boost or not.... You might lose maybe 5k on the lifetime of the turbo, just my guess. But if you think about 60-80k miles on a turbo is a lot in my book..... but I doubt anyone runs stock 7psi any more which probably will give it its longest life.... I am pretty sure anythin about 7 psi on a stock t25 or t28 will reduce its life but eh... its REALLY not a big deal.... Now if you surging on like 15 psi or something.... yeah not good......

Also these are small ass turbos.... its REALLY not pushing that much air therefore when it surges, it really isn't even a big deal....

[Sterlz]

My ssqv does this same thing, its the 2nd generation without the adjuster knob. So I ordered the recirc fitting and recirculated it. That was how I took care of it I guess, it reduced the surge but it didnt get rid of it.

[Mosaic]

Based on my earlier post, the surge problem would be much less if you could have faster reaction times on your valve, Then u could have no flutter and a pressurised intercooler!

I'll share test data with the forum as it comes in!