Flutter after BNR S4 install.

[Atticaz]

So I installed a BNR S4 for about a week ago. After the install I noticed that my Turbosmart bypass valve is fluttering upon release at and above 10psi. It did not flutter with the K0snore. What the shit causes this? K04 was running 20psi... BNR is currently 20ish.

Only change to my setup is:

BNR S4
Bosch 3bar MAP
Grimmspeed 3 port EBCS


Vid of flutter.
https://youtu.be/8rLYv5PU5ok

[tegxsi]

Did the vacuum line on the BPV come off? You would have a big vacuum leak though...

Maybe clean and relube the valve.

[Atticaz]

Originally Posted by tegxsi Did the vacuum line on the BPV come off? You would have a big vacuum leak though... Maybe clean and relube the valve.

That's wait I was thinking. Re-lube. All hoses are snug. The TS BPV is a pain in the ass to open. This'll be fun.

[tegxsi]

Originally Posted by Atticaz That's wait I was thinking. Re-lube. All hoses are snug. The TS BPV is a pain in the ass to open. This'll be fun.

If it's the kompact version I use a rubber or silicone grip thingie... the type that is used to open jars.

[CWP_MS3]

Self-adjusting HKS SSQV4 FTMFW!

I had a turbosmart dual port that I loved, but just could not get it right. Kept causing hesitation and backfires no matter what I did. Finally went back to TurboXS and then SSQV.

[Atticaz]

Originally Posted by tegxsi If it's the kompact version I use a rubber or silicone grip thingie... the type that is used to open jars.

Serviced it today. Wasn't too dirty. I re-lubed it. I'm still getting the same shit. No flutter in low boost... just in boost of around 10psi and higher. I have a call in to Turbosmart, to see what they say. I don't get the BPV was fine with the K04, but is being a picking hooker with the BNR S4.

[CWP_MS3]

Do you have the factory BPV still?

[mituc]

The BPV piston is simply too heavy to flutter because the pressure pushing the piston can't simply vary that fast to make it flutter. I reckon the flutter comes from the wastegate actuator or from the turbo itself. I ran my turbosmart at 26PSI and it didn't flutter. I switched then to the Cobb XLE and I only got some turbo flutter when I made the valve too stiff.

[CWP_MS3]

Yeah, I would try to swap it out and see if its compressor surge.

[zenit]

Originally Posted by mituc The BPV piston is simply too heavy to flutter because the pressure pushing the piston can't simply vary that fast to make it flutter. I reckon the flutter comes from the wastegate actuator or from the turbo itself. I ran my turbosmart at 26PSI and it didn't flutter. I switched then to the Cobb XLE and I only got some turbo flutter when I made the valve too stiff.

That's compressor surge, which is no bueno for a journal bearing turbo.

It sounds like the turbo smart needs a lighter weight oil (sewing oil or lightweight hydraulic oil) and/or a lighter spring.

I was having issues with the turbo smart bpv actuation, similar to what you described. I swapped to a lighter weight spring, and it helped.

I think the mechanism of action with the bpv causing surge, is that you swapped a smaller, more restrictive k04 compressor wheel (produces some vacuum off boost), to a bigger, less restrictive s4 compressor wheel, and now have less vacuum.

[mituc]

The turbosmart BPV is fine (as in properly sized), I've used one with both the factory K04 and with a GTX3071.
The only problem with it was the sealing o-ring which swelled over time, probably from the sewing machine oil I was using. It's really uncommon for a BPV to flutter. the BPV however can start clunking when it opens if it doesn't have lubrication. But it can't flutter!

[Atticaz]

Originally Posted by CWP_MS3 Do you have the factory BPV still?

Originally Posted by mituc The BPV piston is simply too heavy to flutter because the pressure pushing the piston can't simply vary that fast to make it flutter. I reckon the flutter comes from the wastegate actuator or from the turbo itself. I ran my turbosmart at 26PSI and it didn't flutter. I switched then to the Cobb XLE and I only got some turbo flutter when I made the valve too stiff.

Originally Posted by CWP_MS3 Yeah, I would try to swap it out and see if its compressor surge.

It's the Turbosmart BPV. The Street Unit version. Yeah, I can't see the issue being the TS BPV. The spring pressure of TS BPV is noticeable lighter than the OEM BPV and I don't get any flutter at boost. All happens after I let off the gas.

http://www.streetunit.com/Turbosmart...-0997-1009.htm

[Atticaz]

Originally Posted by zenit That's compressor surge, which is no bueno for a journal bearing turbo. It sounds like the turbo smart needs a lighter weight oil (sewing oil or lightweight hydraulic oil) and/or a lighter spring. I was having issues with the turbo smart bpv actuation, similar to what you described. I swapped to a lighter weight spring, and it helped. I think the mechanism of action with the bpv causing surge, is that you swapped a smaller, more restrictive k04 compressor wheel (produces some vacuum off boost), to a bigger, less restrictive s4 compressor wheel, and now have less vacuum.

I have always used CLP gun oil. It's really light stuff. When I cleaned it yesterday, it was still well lubed and piston moved freely. I am waiting for a Turbosmart Rep to call me back. We will see what they say.

[mituc]

Originally Posted by Atticaz It's the Turbosmart BPV. The Street Unit version. Yeah, I can't see the issue being the TS BPV. The spring pressure of TS BPV is noticeable lighter than the OEM BPV and I don't get any flutter at boost. All happens after I let off the gas.

Mine was the SU version as well, I purchased it back in 2010.

[Atticaz]

Originally Posted by mituc Mine was the SU version as well, I purchased it back in 2010.

I'm lost here. I was speaking to another speed owner that has a TS BPV and BNR S3, she said hers does the same. I still have my OEM BPV. I also have the optional stronger Trubosmart spring (pink). I may give those both a try, while waiting for the Rep to get back to me.

[zenit]

Originally Posted by Atticaz I'm lost here. I was speaking to another speed owner that has a TS BPV and BNR S3, she said hers does the same. I still have my OEM BPV. I also have the optional stronger Trubosmart spring (pink). I may give those both a try, while waiting for the Rep to get back to me.

Get a green or blue spring.
OEM and TS bpv springs cannot be compared, as they function differently.

[mituc]

The pink spring is too stiff, use the green one.
A stiffer spring will not hold boost better as the BPV does not open under boost (at least not at these boost values we run them at, say below 30PSI), it will only dictate how fast and soon the BPV will open when you let off the acceleration, and in these conditions you want it to open as fast as possible.

[Atticaz]

Originally Posted by mituc The pink spring is too stiff, use the green one. A stiffer spring will not hold boost better as the BPV does not open under boost (at least not at these boost values we run them at, say below 30PSI), it will only dictate how fast and soon the BPV will open when you let off the acceleration, and in these conditions you want it to open as fast as possible.

The green one is in there.

[Atticaz]

So I put my stock BPV in. Flutter is gone. Also all the excessive exhaust piping I've been getting is gone. I think I need a completely different BPV definitely. I got tired of waiting around for turbosmarts reply.

EDIT: Stock BPV is not holding full boost. Current revision is at 21PSI. Only hitting 19.2.

[Code Monkey]

Originally Posted by Atticaz I was speaking to another speed owner ..., she said

Pictures or gtfo.

[Atticaz]

Originally Posted by Code Monkey Pictures or gtfo.

HAHAHHAAHHAAAAA. *Cries as walking out.* *door slams*

[Atticaz]

@Code Monkey; What BPV you running with your S3? I just have the full recirc one now, with the green spring (the one that is supposed to be for the MS3/MS6/CX-7). As stated above, I put my OEM BPV back to check shit out and flutter is gone. It's not holding full boost pressure (about 90ish%). But, I am thinking I need to get a different one.

[Code Monkey]

Synapse DV.

[Atticaz]

Originally Posted by Code Monkey Synapse DV.

I take it, no issues... and you love it. I need to get rid of this flutter. I HATE it. I'll check this one out.

I'm trying to decide if I wanna try the new CS VTA BPV, the Turbosmart Dual Port, GFB 50/50 or..... Current one is NOT cutting it.

[mituc]

Maybe your BPV piston doesn't move properly and that's why you get the flutter, and that's why the flutter got away with the factory BPV. So you just need a new BPV and yes, whatever you get keep it in full recirc.

[zenit]

OEM uses a lightweight plastic piston and under low vacuum cracks open a hair (kind of like a synchronic BPV's).

It also tends to leak at the assembly seam.

[Atticaz]

Originally Posted by zenit OEM uses a lightweight plastic piston and under low vacuum cracks open a hair (kind of like a synchronic BPV's). It also tends to leak at the assembly seam.

Yeah. I already took it out.

[Atticaz]

Originally Posted by mituc Maybe your BPV piston doesn't move properly and that's why you get the flutter, and that's why the flutter got away with the factory BPV. So you just need a new BPV and yes, whatever you get keep it in full recirc.

It's unbelievable. Yesterday I called Turbosmart USA directly. They said the tech guy was busy and they'd call me back. I even messaged them on Facebook. Got a reply to email them, if I had a tech question. Still no reply.

I also messaged BNR, just to see what their thoughts were on the matter, since it "does' involve one of their products. No reply.

I'm gonna give the new Corksport VTA BPV a chance. It only vents to atmosphere at high boost. Wish me luck. I'll report back, when I get and install it.

[mituc]

Don't VTA, just stay full recirc.

[impossible]

Surprised no one asked this but how often are you maintenancing your push type bov?

[sharksinspace]

Originally Posted by mituc Don't VTA, just stay full recirc.

FWIW, the CS dual-port is only VTA at higher boost pressures, and even then I think it's still only partly VTA. They say it requires no tweaks to your tune to run properly (reviewers report no issues with richness) and won't mess with idle, etc. Personally, I'd love to give the thing a try but I already have their original BPV and can't justify dropping almost $300 just for it to make different sounds.

[Atticaz]

Originally Posted by impossible Surprised no one asked this but how often are you maintenancing your push type bov?

Every oil change. I did and extra cleaning the day before yesterday.

Flutter after BNR S4 install.

[tegxsi]

I had the original CS BPV and didn't like how it didn't have an air tight seal when closed. The new VTA version as a gasket at the piston seat which is better.
Does the new CS VTA valve still use that "wave" spring that like breaks into 2-3 pieces?

[mituc]

Originally Posted by sharksinspace FWIW, the CS dual-port is only VTA at higher boost pressures, and even then I think it's still only partly VTA. They say it requires no tweaks to your tune to run properly (reviewers report no issues with richness) and won't mess with idle, etc. Personally, I'd love to give the thing a try but I already have their original BPV and can't justify dropping almost $300 just for it to make different sounds.

VTA at any boost level is not that good. It means (probably only marginally) hotter exhaust gases, more soot therefore higher chances for getting hot spots, and some extra fuel in the cylinders which at that high boost - so high piston and cylinder temps - will also thin out or even wash away the oil film from the cylinder walls.
So no, only full recirc is a viable option.

[sharksinspace]

Originally Posted by tegxsi I had the original CS BPV and didn't like how it didn't have an air tight seal when closed. The new VTA version as a gasket at the piston seat which is better. Does the new CS VTA valve still use that "wave" spring that like breaks into 2-3 pieces?

I don't know if the dual-port uses the wave design, but Vincent told me when I needed a replacement spring that they've worked with the manufacturer to start making them out of a stronger material; breaking shouldn't continue to be a problem, going forward.

Originally Posted by mituc VTA at any boost level is not that good. It means (probably only marginally) hotter exhaust gases, more soot therefore higher chances for getting hot spots, and some extra fuel in the cylinders which at that high boost - so high piston and cylinder temps - will also thin out or even wash away the oil film from the cylinder walls. So no, only full recirc is a viable option.

Blah, blah, blah. Look man, I respect your level of knowledge but how many guys are running at least partial VTA with little or no problem? If you want to run full recirc forever, more power to you, but it does not appear to be "the only viable option."

[mituc]

Originally Posted by sharksinspace Blah, blah, blah. Look man, I respect your level of knowledge but how many guys are running at least partial VTA with little or no problem? If you want to run full recirc forever, more power to you, but it does not appear to be "the only viable option."

I'm only trying to steer people in the right direction to do things right. If it's "blah blah" for you that's a different story. I know this kind of statements "I'm doing this and I've never had a problem" or "Used this with no problem". The fact that someone never had a problem so far doing something wrong doesn't mean it's the new correct approach.

These cars generate and build a lot of soot in various places in the engine. Running very rich at low load even for short amounts of time makes this issue a lot worse. The soot build-up is one of the reasons for cracked ringlands on otherwise stock cars. If you don't care about yours because you intend to sell it within the next 1-2 years doesn't mean that others don't care either.

So if you want to do something only for the show maybe other people are interested in applying the "blah blah" correctly. So let people hear both sides of the story and have them decide for themselves if they only want to blip the throttle in parking lots at 2000rpm to draw attention with that PSHHH PSHHH, or want the full enchiladas from their engine both in therms of power and longevity.

[sharksinspace]

I don't take issue with your desire to explain why you think full recirc is a better option (and I happen to agree for the most part, realistically); I take issue with your referring to it as "the only viable option." That's not presenting both sides, that's presenting one side and declaring out of hand that the other is inherently incorrect.

I wouldn't run full VTA on this car, and the BPV I've got is full recirc, but I think it's a bit hyperbolic to act like using a valve that is partial VTA under only certain circumstances, while otherwise being recirc, is such a hugely detrimental decision.

[Atticaz]

Originally Posted by tegxsi I had the original CS BPV and didn't like how it didn't have an air tight seal when closed. The new VTA version as a gasket at the piston seat which is better. Does the new CS VTA valve still use that "wave" spring that like breaks into 2-3 pieces?

I messaged Luke to find out. He said:

"The new valve doesnt use a wave spring. We used a much stronger spring this time around"

[Atticaz]

Originally Posted by mituc I'm only trying to steer people in the right direction to do things right. If it's "blah blah" for you that's a different story. I know this kind of statements "I'm doing this and I've never had a problem" or "Used this with no problem". The fact that someone never had a problem so far doing something wrong doesn't mean it's the new correct approach. These cars generate and build a lot of soot in various places in the engine. Running very rich at low load even for short amounts of time makes this issue a lot worse. The soot build-up is one of the reasons for cracked ringlands on otherwise stock cars. If you don't care about yours because you intend to sell it within the next 1-2 years doesn't mean that others don't care either. So if you want to do something only for the show maybe other people are interested in applying the "blah blah" correctly. So let people hear both sides of the story and have them decide for themselves if they only want to blip the throttle in parking lots at 2000rpm to draw attention with that PSHHH PSHHH, or want the full enchiladas from their engine both in therms of power and longevity.

For the record: I'm not buying it for the sound, but for function; no other reason. Everyone has their opinions and are entitled to them. I've done my research. I'm good with my choice. We'll see how things turn out after install.

[Atticaz]

So I have had the Corksport dual VTA BPV in for about a week and a half. Flutter is gone.

I am digging this BPV. The VTA sound isn't overbearing at all. The only thing that bugged me is the BPV has a sequence of whistles it makes as its releasing lower pressures. Luke at Corksport and I call it the mockingjay. lol. Its annoying at first. But it grows on you. I thought there was an issue with it. But, turns out its a byproduct of the piston design.

Here's a vid I made.

https://youtu.be/tEsvlybAhoU