The importance of the BPV

[Mauro_Penguin]

Originally Posted by Lex 1. Valve speed 2. Does it need to be serviced or lubricated. I am not a fan of these types of valves as they "lose" performance as the lube wears. 3. Reliability - are there wear or breakable items like diaphragms? 3. Adjustability 4. Fit and quality 5. I prefer push design for least surge

Its very hard to get a hold of a lot of this info without contacting manufacturers and going through web site secretaries. As someone stated earlier, our community has regarded bpv's as more of a high boost necessity or "rice sound" mod so it is hard to put them all back to back I suppose. Not a whole lot of info on response time.

I completely agree with you about the reliability and service being a big note to take when shopping around, but I was under the impression though that all aftermarket bpv's needed to be lubed?

[Lex]

Originally Posted by Mauro_Penguin Its very hard to get a hold of a lot of this info without contacting manufacturers and going through web site secretaries. As someone stated earlier, our community has regarded bpv's as more of a high boost necessity or "rice sound" mod so it is hard to put them all back to back I suppose. Not a whole lot of info on response time. I completely agree with you about the reliability and service being a big note to take when shopping around, but I was under the impression though that all aftermarket bpv's needed to be lubed?

I am curious how many manufacturers do this kind of testing altogether. All the non diaphragm valves will need some lubrication at some point but diaphragm valves are generally slower and they do fail over X cycles.

The truth is that tuning pressure systems mechanically is a bit of an art. Component responses will affect what works and what doesn't and that includes the turbo, piping, WG, etc.

I experienced some pretty bad SWAS interaction once I swapped out the OEM BPV and installed the BNR. The spool and airflow rates of the BNR, the response of the BPV and the DSC/SWAS systems were not well in tune/calibrated with each other. Even when SWAS was not involved I felt the response was sluggish when transitioning on and off the throttle. Before cutting the wire to SWAS which many people opt for I wanted to give it another shot with a faster BPV and it worked well.

[ledfootrob]

Lex i recently installed a BNR S3 and started getting SWAS intervention. I thought at the time my GFB Response might have something to do with it so i put the stock BPV back on which didn't change anything. Now i have to long press the DSC button everytime i drive my car so i dont get SWAS'd and dont get a CEL (Rich Condition Bank 1).
Did you test the OEM BPV with the BNR and still get SWAS'd
Looking at swapping to a Synapse now if you think it'll solve my issue.

[garf]

good read, never had a bpv in a car before so more info is always welcome!

[cletusb]

Regarding the synapse in push or pull mode. I thought I remembered reading that the push mode was only good to, I'm guessing here, 20psi and after that they recommended the pull set up

[Lex]

Originally Posted by ledfootrob Lex i recently installed a BNR S3 and started getting SWAS intervention. I thought at the time my GFB Response might have something to do with it so i put the stock BPV back on which didn't change anything. Now i have to long press the DSC button everytime i drive my car so i dont get SWAS'd and dont get a CEL (Rich Condition Bank 1). Did you test the OEM BPV with the BNR and still get SWAS'd Looking at swapping to a Synapse now if you think it'll solve my issue.

It sounds like there can be more things happening aside from the BPV if you are getting a CEL as well. Boost leaks can also cause SWAS like bucking issues. I did use the OEM with the BNR and while it was better than the aftermarket (aside from the fact that it bled boost) it didn't address the issue as well as the Synchronic. My suspicion is because the OEM turbo has a faster spool time/response time than any of the larger turbos.

Originally Posted by cletusb Regarding the synapse in push or pull mode. I thought I remembered reading that the push mode was only good to, I'm guessing here, 20psi and after that they recommended the pull set up

The valve will seal up to 60psi in either configuration according to their documentation.

This is not meant to be a product advert, it's meant to be informative. I haven't tested all the valves on the market and combinations of parts. I wanted to draw attention to the BPV as being a culprit to some of the driveability issues we experience.

[ledfootrob]

I only get a CEL after the SWAS makes my car run rich a few times. I definently dont have a boost leak, been tested multiple times.

Sent from my GT-I9300 using Tapatalk 2

[Pitchblackzoom]

what good info most people just go for the swoosh sound and dont even think twice before rice hahah

[himurax13]

Well I have been driving around for a week on my Forge V1 with a green spring and one shim instead of blue with 1 shim on 20 lbs of boost.

The Forge reacts much faster than before and I can hear the sword clash more clearly. The bucking in third gear near redline in the corners has also been reduced.

I might try removing the shim and take some 4th gear logs to see if I am still holding boost.

[Lex]

Originally Posted by himurax13 Well I have been driving around for a week on my Forge V1 with a green spring and one shim instead of blue with 1 shim on 20 lbs of boost. The Forge reacts much faster than before and I can hear the sword clash more clearly. The bucking in third gear near redline in the corners has also been reduced. I might try removing the shim and take some 4th gear logs to see if I am still holding boost.

The forge will hold boost even without a spring since the surface area on the top of the piston is quite a bit larger than on the bottom of this piston. Give it a shot with the softest spring .

[himurax13]

Originally Posted by Lex The forge will hold boost even without a spring since the surface area on the top of the piston is quite a bit larger than on the bottom of this piston. Give it a shot with the softest spring .

Which one is the softest? The yellow?

It is funny hearing the sword clash almost immediately after throttle lift.

[Lex]

Originally Posted by himurax13 Which one is the softest? The yellow? It is funny hearing the sword clash almost immediately after throttle lift.

The green I believe.

[hnda etr]

Originally Posted by Lex I mentioned the importance of the BPV earlier this year and finally got to do some testing with one of the fastest valves on the market. The results were great. SWAS and stability control no longer got in the way. No more bucking, loss of boost, jerkiness when taking a hard corner in a lower gear. So if you want SWAS and the stability control to work with you and not against you, get a BPV that is as fast as possible. A fast valve also helps response and spool.

It's nice to see someone as respected as Lex recognize the Synapse DV. I was probably one of, if not The First person to run the DV after switching over from their regular BOV.

Got some shit from Haltech and others about it, but I think they've more than proven themselves as legit: Synapse Engineering's new Synchronic Diverter Valve

Edit: Now I need to make sure I'm running in Push mode and not Pull...

Edit 2: Yup, running in Pull mode... Maybe this explains the issues I have been having with the stuttering/cutting, especially around corners lol. Cld12pk2go told me to disconnect the SWAS so I'll be doing that too Saturday...

[uncorked11]

Originally Posted by Lex I have never tested the COBB unit so it's hard to give you a comparison. I also don't know how it is designed internally. Pretty much any aftermarket valve will hold boost by design so that's not a concern. I would look at a few things: 1. Valve speed 2. Does it need to be serviced or lubricated. I am not a fan of these types of valves as they "lose" performance as the lube wears. 3. Reliability - are there wear or breakable items like diaphragms? 3. Adjustability 4. Fit and quality 5. I prefer push design for least surge

Originally Posted by Mauro_Penguin @Lex; how would you say the synapse DV compares to the cobb bpv? I understand the configuration on the synapse can change from push to pull, but I mean in a apples to apples set up, how is the response and stability between the two? Just curious as I was sold on the cobb unit for my future upgrade list.

I had a Cobb before my HKS.

1.It was quick when clean other wise the change over from OEM was seamless.
2. Required moly lube at oil change intervals (4000 miles of 70/30 highway driving).
3. Insides contained a push type aluminum cap with one O-ring. One spring and washer attachment for adjustment screw.
4. Adjustable via Allen key and 10 mm wrench. To much spring pressure can lead to mild surge when releasing throttle at mild boost.
5. Typical Cobb quality. Overbuilt, works fabulous in recirc, didn't want to mess with it much in VTA.

I liked it but I decided to go a different route. That being said I have been SWAS delete for 2 years.

[Lex]

Originally Posted by hnda etr It's nice to see someone as respected as Lex recognize the Synapse DV. I was probably one of, if not The First person to run the DV after switching over from their regular BOV. Got some shit from Haltech and others about it, but I think they've more than proven themselves as legit: Synapse Engineering's new Synchronic Diverter Valve Edit: Now I need to make sure I'm running in Push mode and not Pull... Edit 2: Yup, running in Pull mode... Maybe this explains the issues I have been having with the stuttering/cutting, especially around corners lol. Cld12pk2go told me to disconnect the SWAS so I'll be doing that too Saturday...

The DV should have as little preload as possible and it should be lubricated at some point although they don't mention an interval.

Also make sure the cuts are not spark related. The car commands very rich mixtures under SWAS conditions and those alone can cause blowout.

With the OEM turbo, 2 port, and OEM valve SWAS does not interfere much with the driving experience. As you change these parts the calibration of the DSC system is off from the hardware installed and it becomes more of a problem. The 3 parts I mentioned above play a big role.

[hnda etr]

Originally Posted by Lex The DV should have as little preload as possible and it should be lubricated at some point although they don't mention an interval. Also make sure the cuts are not spark related. The car commands very rich mixtures under SWAS conditions and those alone can cause blowout. With the OEM turbo, 2 port, and OEM valve SWAS does not interfere much with the driving experience. As you change these parts the calibration of the DSC system is off from the hardware installed and it becomes more of a problem. The 3 parts I mentioned above play a big role.

I checked and I've got 0 preload. I ran into a problem taking the DV apart last night though. Looks like last time I took the thing apart to clean and lube it (probably 1.5 years ago), I tightened the little hex bolts too much and 2 of them stripped their heads. So now I can't take it apart. I dripped some of the lube on the piston and made sure that it moved freely and even after 1.5 years, the piston was clean and moved freely even before the additional lube.

I reinstalled the valve in push mode and left the SWAS connected so I can see if there's any change. Spark blow out is probably not an issue with me - I'm running a 0.026" gap along with the HKS twin fire. Plugs have around 12k miles on them so i will probably change them next weekend.

I did raise the starting threshold on my DO wmi controller though a while back, to start at around 7 psi and go full blast at 10 psi. I was thinking that blowout might be happening because I was starting to airway around 5 psi... didn't help though.

Edit: as for the lube interval, synapse says they put the DV through a 1 million cycle test with no issues... I doubt I did 1/4 of that in the last 1.5 years lol https://www.youtube.com/watch?v=Q2dw...e_gdata_player

[hnda etr]

Quick update.. Called Synapse today and they're gonna send me a loaner to use so I can send them my DV to have the seized bolts removed... No problem at all from them!

[hnda etr]

Ended up unplugging the SWAS yesterday, and putting a switch in today, and what a difference! Definitely more performance when disabled and that f'ing cutting out is gone when disabled!

[hnda etr]

Proof the Synapse guys have a sense of humor... notice the hand drawn stripper pole, disco ball, flood light and the "made it rain" bills on the floor lol.

Fyi - they sent me a loaner DV, removed the stripped bolts from my DV, serviced it and returned it to me - they also paid all the shipping both ways! I paid exactly $0 to have my DV repaired. Nice!

@Lex; you get my PM? Or you just ignoring it?

[Lex]

Originally Posted by hnda etr Proof the Synapse guys have a sense of humor... notice the hand drawn stripper pole, disco ball, flood light and the "made it rain" bills on the floor lol. Fyi - they sent me a loaner DV, removed the stripped bolts from my DV, serviced it and returned it to me - they also paid all the shipping both ways! I paid exactly $0 to have my DV repaired. Nice! @Lex; you get my PM? Or you just ignoring it?

Response by end of day, I promise

[Zbrit00x]

the synapse dv is awesome, it fixed all my response/bucking surge issues and the support from the synapse guys was awesome when a bolt snapped and serviced my valve when I could have just used thread seal tape on the top 2 ports ( leaked very little at 20psi when leak tested)

[p057]

i got the synapse DV recently too. I wanted a new BPV that wasnt loud and annoying like the forge, responds quickly, and doesnt need maintenance.
so far I'm really happy with it! it's extremely quiet and reacts fast! However, i left the preload at whatever the hell level it is out of the box. is that considered zero? should I unscrew the nut more? I think it's running fine as-is and probably should leave it alone.

Push mode, A+B, stock spring preload.

[hnda etr]

Originally Posted by p057 i got the synapse DV recently too. I wanted a new BPV that wasnt loud and annoying like the forge, responds quickly, and doesnt need maintenance. so far I'm really happy with it! it's extremely quiet and reacts fast! However, i left the preload at whatever the hell level it is out of the box. is that considered zero? should I unscrew the nut more? I think it's running fine as-is and probably should leave it alone. Push mode, A+B, stock spring preload.

out of the box setting is zero preload I believe... you can always double check it by loosening the locking nut and seeing if the hex bolt will unscrew any more (counter clockwise)

[p057]

Originally Posted by hnda etr out of the box setting is zero preload I believe... you can always double check it by loosening the locking nut and seeing if the hex bolt will unscrew any more (counter clockwise)

i unscrewed it, the nut just went up the shaft of the bolt/stud/whatever. the shaft didnt move, so i "re-tightened" it down to it just being up snug to the bpv, no extra torquing.

been fine like that.

[hnda etr]

Originally Posted by p057 i unscrewed it, the nut just went up the shaft of the bolt/stud/whatever. the shaft didnt move, so i "re-tightened" it down to it just being up snug to the bpv, no extra torquing. been fine like that.

The shaft should have a tiny hex depression in it. The nut is just a locking nut. You have to loosen the locking nut and then insert a small hex wrench into the top of the shaft and turn it...

Synapse Engineering's new Synchronic Diverter Valve

[Lex]

Zero preload is out of the box. A+B in push mode works very well.

[Tomas]

ALex, I thought you were happy with your Forge. So do you really like the Synapse that much better?
Fuck I've tried Turbosmart, HKS, and greddy and don't like any of them. Part throttle response is horrible. On all of them. Stock is the only one with good part throtle response but at 25 psi it leaks like hell.

[Lex]

Originally Posted by Tomas ALex, I thought you were happy with your Forge. So do you really like the Synapse that much better? Fuck I've tried Turbosmart, HKS, and greddy and don't like any of them. Part throttle response is horrible. On all of them. Stock is the only one with good part throtle response but at 25 psi it leaks like hell.

After using the Synapse I wouldn't go to the other mainstream brands. The response is as quick as stock if not quicker so you should be happy with it. Definitely faster than the Forge which had to be constantly lubricated.

[bioevolve]

That Vibrant Performance DV looks awfully the same as the Synapse DV.
Is it a picture mistake?

Edit: no picture mistake.
Wonder who is the manufacturer?!?!?! One or the other or neither of them lol?
There is about a $20 difference between them.
Either way, I'm gonna get one.


Synapse:


Vibrant:

[Lex]

The important bits are what's on the inside. With just a $20 difference I would stick with the original.

[p057]

this might explain that?

EvoXForums.com - Mitsubishi Lancer Evolution X Forums - View Single Post - Synapse DV vs Vibrant DV?

[cletusb]

Yeah I always thought the vibrant ones were just rebadged or mislabled

[PhorB13]

Lex, what are you opinions on the CorkSport BPV? I'm interested in hearing your thoughts.

[Lex]

Originally Posted by PhorB13 Lex, what are you opinions on the CorkSport BPV? I'm interested in hearing your thoughts.

Unfortunately I don't have any direct experience with that BPV personally.

[PhorB13]

Originally Posted by Lex Unfortunately I don't have any direct experience with that BPV personally.

I should let you test mine... hmmm

[Lex]

Another important and quick note about bypass/blow off valves. In general they don't add too much to power unless you're running 20+psi on the MazdaSpeeds. At that point pretty much all OEM valves start to open and bleed pressure. On a big turbo car this can be a little hard to detect. The car will still hold boost but airflow (g/s) values will seem low as will power. On the car below we are in the middle of a pump gas tune on a BNR S3. The motor has a lot of miles on it and is knock prone but you can see what replacing the OEM BPV did here. So for above 20psi applications and all big turbo ones, it's wise to run an aftermarket bypass valve.

[Cheapspeed]

@Lex; any experience tuning with the corksport bpv? I just want to know that it'll hold boost on a gtx3076 at a low 380hp. It's definitely priced well, but I haven't found specs on what kind of pressure it will hold.

[Lex]

Originally Posted by Cheapspeed @Lex; any experience tuning with the corksport bpv? I just want to know that it'll hold boost on a gtx3076 at a low 380hp. It's definitely priced well, but I haven't found specs on what kind of pressure it will hold.

I haven't personally used it and while I have tuned cars using it, shifting and on/off throttle applications are where a BPV shines or falls short.

Boost pressure is what it has to hold, not crack open regardless of turbo used and I haven't heard or seen issues with it holding pressure. If it leaks you will see an unreasonable drop in power and no airflow rise in the upper RPM as boost goes up.