HKS SSQV V3 Is too big for the MS6 Hood - cuts vacuum line

[FORZDA 1]

You sure? Because im pretty sure its air going back into the the turbo causing compressor surge or something? Yea mines not adjustable..
It made the same sound but worse when the vacuum line got cut off.. So im positive it was air going back into the turbo.

Maybe your right though

Blendercloud is correct in the BPV bouncing and relieving/trapping pressure, but that pressure wave is applied back to the compressor as well. In most cases of mild bounce(flutter) the turbo doesn't actually have a compressor stall, but it "could" if the backpressure pulse is hard enough. What I prefer to prevent is ALL the BPV bounce/flutter which is what the OEM BPV is designed to do. Mazda knew the effects of poor pressure control and used a very good diaphram design that works extrremely well.

I will pay postage/shipping (US only) for anyone's OEM BPV up to ~5 or so. I need a spare and I'll do some functional verification on them...

 

[Blendercloud]

I can see how the compressor might experience turbulence during "flutter", but I still disagree with the phrase "air going back into the turbo". Essentially, the turbulance created by the BPV/BOV piston's position fluctuating during "low flow" would create erratic changes in the velocity of boosted air. At that point, the turbo would be experiencing fluctuating pressure on the compressor.

Not trying to be argumentative here. I'm just trying to spell it out because I actually thought you meant you thought air was physically going backward in the system.

 

[FORZDA 1]

I can see how the compressor might experience turbulence during "flutter", but I still disagree with the phrase "air going back into the turbo". Essentially, the turbulance created by the BPV/BOV piston's position fluctuating during "low flow" would create erratic changes in the velocity of boosted air. At that point, the turbo would be experiencing fluctuating pressure on the compressor.

Not trying to be argumentative here. I'm just trying to spell it out because I actually thought you meant you thought air was physically going backward in the system.

Yeah, it's kind of a misnomer about the air going backwards. There are pressure waves inside the manifold, intercooler, etc. that can essentially block the turbo compressor outlet. You're correct in that the air doesn't actually flow "backwards".

 

[Blendercloud]

The idea of air flowing backward through my induction system reminds me of those horror movies that have scary little kids walking backward all funny.

I don't know how that relates, but yea.

 

[FORZDA 1]

I never said anything like that.. I said the hks is made like crap!! .......

I do appologize as I miss-represented what you posted. Here is what you said:

............ And stock won't hold any turbo pressure past 5k rpms.......

 

[batou079]

It isn't that "all stock MS6 BPVs" are crappy, it's that they have a track record of leaking.
Whether it be internals or fitment/flange seating, mark is getting at the fact that many are reported to leak in high RPMs.

Mine most certainly did, would spike, then instead of hold.. would drop PSI FAST.
Switching to the Turbosmart BPV, i spike then hold at 15+ PSI. btw i have to laugh at the people that pay 350+ bux for the hybrid TS BPV... lol.

 

[FORZDA 1]

It isn't that "all stock MS6 BPVs" are crappy, it's that they have a track record of leaking.
Whether it be internals or fitment/flange seating, mark is getting at the fact that many are reported to leak in high RPMs.

Mine most certainly did, would spike, then instead of hold.. would drop PSI FAST.
Switching to the Turbosmart BPV, i spike then hold at 15+ PSI. btw i have to laugh at the people that pay 350+ bux for the hybrid TS BPV... lol.

If you still have it please send it to me! Thanks!

 

[8.5MS3]

i got my hks because MY oem valve was leaking, no issues whatsoever with the hks. and its not that the stock bpv cant hold boost at high revs, if it holds 15psi down low it will hold it up top, pressure is independent of rpm 15psi is 15psi, its that the stock tune reduces boost over 5500 because the turbo cant keep up. 75whp at redline sucks ass

also, as for the hks flutter, at lower revs it tends to flutter, but this is more due to the staged release of air. there are 2 valves that open and close in sequence, during low boost you have enough to open the primary, maybe the secondary (first flutter), then the secondary closes (2nd flutter) followed by the primary. If the boost is ramped down slowly, such as easing up on the pedal but not taking your foot off, the secondary will open and close repeatedly, causing a longer flutter sound

 

[batou079]

lol send you my OEM BPV? no.
i keep my stock parts.

 

[FORZDA 1]

lol send you my OEM BPV? no.
i keep my stock parts.

So you want to keep an obviously bad part? I'll send it back to you when I finish testing it. Thanks!

 

[KrGsMrNKusinagi]

i got my hks because MY oem valve was leaking, no issues whatsoever with the hks. and its not that the stock bpv cant hold boost at high revs, if it holds 15psi down low it will hold it up top, pressure is independent of rpm 15psi is 15psi, its that the stock tune reduces boost over 5500 because the turbo cant keep up. 75whp at redline sucks ass

also, as for the hks flutter, at lower revs it tends to flutter, but this is more due to the staged release of air. there are 2 valves that open and close in sequence, during low boost you have enough to open the primary, maybe the secondary (first flutter), then the secondary closes (2nd flutter) followed by the primary. If the boost is ramped down slowly, such as easing up on the pedal but not taking your foot off, the secondary will open and close repeatedly, causing a longer flutter sound

Thanks man you explained it perfectly.. I was just wondering though because on my Beetle I never had any flutter at ALL on the same HKS valve.. In fact I have never had flutter from any turbo car I have had except for this one. Thats what made me wonder.

But What your saying makes sense

 

[zinger002]

i thought the stock bpv leaked on the tubing side because my (cheap) believed to be accurate boost gauge would only read 11-12 but the cobb ap and my dash hawk both read 14-15 hold.

 

[batou079]

So you want to keep an obviously bad part? I'll send it back to you when I finish testing it. Thanks!

hell yes. if i ever have to go back to stock... leaky is still stock. lol
Hmmm id definitly like to test it further to see if its my specific OEM BPV that was bad...

anyway to do that off the car?

 

[FORZDA 1]

hell yes. if i ever have to go back to stock... leaky is still stock. lol
Hmmm id definitly like to test it further to see if its my specific OEM BPV that was bad...

anyway to do that off the car?

You can test the diaphram function for leaks with a simple pressure/vacuum pump like a Mity-Vac brake bleeder or similar. The diaphram should hold pressure or vacuum from the vacuum/boost line nipple. The main seal however, must be tested on the car or you'll need to set up something to seal and pressurize the main flange hole and the opening back to the intake tube.

Note that manifold boost and vacuum is applied to the diaphram (and piston top in other BPVs) through the nipple to assist in closing and opening the BPV. If you have a leak in the vacuum/boost hose or even your boost gauge connection, you will have a vacuum leak at idle and a boost leak under boost which will let lessen the boost assist on top of the diaphram and subsequently the BPV will release manifold pressure before it should.

 

[8.5MS3]

Thanks man you explained it perfectly.. I was just wondering though because on my Beetle I never had any flutter at ALL on the same HKS valve.. In fact I have never had flutter from any turbo car I have had except for this one. Thats what made me wonder.

But What your saying makes sense

heres a vid of a turbo z with the hks fluttering. its also very dependent on your vacuum source, the length of tubing to the valve, etc.

http://www.youtube.com/watch?v=-PsebphGe6w

 

[bova80]

half throttle:
http://www.youtube.com/watch?v=ZJx6uqE1o6k

full throttle:
http://www.youtube.com/watch?v=jrQCZKv2j5Q

 

[8.5MS3]

^^yup that sounds bout right^^ like the exhaust tone too

 

[KrGsMrNKusinagi]

Well I went back and put my HKS SQV2 on and it does not make the noise near as much and its also alot quiter when I do hear it.

Im thinking the SQV3 is stiffer

 

[speed6lukasz]

so i bought a hks from a guy on here.....and im pretty much furious. i put it on and i saw that the nipple wasent going to fit. so then i moved it down so it would. now its all flutter flutter flutter. which leads me to think compressor surge. any help. and yea i did check all the hoses etc. i even sprayed a lil soap on the connections to see if ANY air is getting out. none what so ever. this only leads me to think its a defective unit which is y this guy sold it.

 

[speed6lukasz]

oh yeah and it sounds exactly like this when i drive. in all rpms however the higher the rpms the quicker and shorter the flutter is. http://www.youtube.com/watch?v=ZJx6uqE1o6k however it is still there.