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Old 09-11-2022, 08:34 AM   #1
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atmoshpere/recirc bov with z32 maf sr question

I guess I'm a little ricey at heart because I miss the bov sounds, can we use a bov that recirculates AND bleeds off too atmosphere with a z32 maf on sr20det or will it stall out after boosting?will this supply enough air to maf to make it happy or em i stuck recirculated bov only?
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Old 09-11-2022, 04:52 PM   #2
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Originally Posted by spools420a View Post
I guess I'm a little ricey at heart because I miss the bov sounds, can we use a bov that recirculates AND bleeds off too atmosphere with a z32 maf on sr20det or will it stall out after boosting?will this supply enough air to maf to make it happy or em i stuck recirculated bov only?
Convert to MAP and you can have all the ricer sounds.
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Old 09-11-2022, 05:00 PM   #3
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You can switch to aluminum intake piping, it'll help amplify the sound vs. the rubber intake hose. I mean, you can vent to atmosphere with a MAF, I did for years, it'll just run a little meh for a second between shifts. Keep in mind that this is coming from a person who is now switching to MAP and is recirculating his BOV. I'll let the younger guys make all the noise.
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Old 09-11-2022, 09:57 PM   #4
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If you release air that the maf previously read the engine runs excessive rich,

the extra fuel washes down oil from the cylinder walls and leads to excessive ring wear and low compression over 10 to 20 years as evinced by the myriad vehicles I've witnessed it happen to

Recirculate to protect the engine.

Also recirculation conserves kinetic energy by returning air molecules with organized vector velocity components to the compressor. This in turn improves compressor pressure ratio and improves spool character for any rpm including off idle.
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Old 09-12-2022, 08:18 AM   #5
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I have the HKS SSQV S14/15 kit with the recirculation bung along with an Apexi induction pipe, BOV sound is pretty loud, but comes from the driver's side now lol. So the comment above about aluminum piping certainly has some merit.
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Old 09-13-2022, 11:44 AM   #6
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Originally Posted by LoSt180 View Post
I have the HKS SSQV S14/15 kit with the recirculation bung along with an Apexi induction pipe, BOV sound is pretty loud, but comes from the driver's side now lol. So the comment above about aluminum piping certainly has some merit.
Of course it does. Rubber doesn?t do well with acoustic vibrations and resonance.
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Old 09-13-2022, 01:09 PM   #7
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fwiw i have blacktop with maf with a ssqv vented to atmosphere and have no issues. between shifts or otherwise
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Old 09-13-2022, 06:42 PM   #8
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fwiw i have blacktop with maf with a ssqv vented to atmosphere and have no issues. between shifts or otherwise
1. SSQV does not hang open at idle nor does it release much if any airflow at low pressure, say 0 to 5psi. Instead, it forces compressor into surge condition which will wear out the turbocharger.

2. The OEM and PFC ecu have a fuel cut for TPS conditional < 1.5%? above roughly 1400rpm which means while the bypass is open there is no issue with overfueling the engine in my experience even with a maf sensor.

The issue with overfueling occurs on push-type bypass (like factory style) where it can hang open under 1400rpm preventing surge, the maf tries to idle the engine and the leaking air causes excess fuel and idle issues.

Correct solution is push style bypass recirculated, prevent surge, prevent over fuel condition. SSQV is a trade off, you give up turbocharger lifespan for the atmospheric blow off affect. Indeed we installed hundreds of SSQV back in the day because we knew it would keep the engine running smooth despite being atmospherically vented. However you can easily hear the surge conditional and now understand it means excess compressor wear.
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Old 09-14-2022, 08:50 AM   #9
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Quote:
Originally Posted by burnsauto View Post
I mean, you can vent to atmosphere with a MAF, I did for years, .
i cant,ever since i upgraded to a 2871r and needed to use a z32 maf it will stall everytime i come out of boost and let off the gas.
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Old 09-14-2022, 09:06 AM   #10
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Originally Posted by jr_ss View Post
Convert to MAP and you can have all the ricer sounds.
there are two types of people in here,ones who admit they like bov sounds and others who pretend they dont like the sounds to go along with the herd.

deep down were all gear heads who love these turbo sounds even if we dont admit it.

mine makes zero sound,im not looking for "hey everyone look at me" obnoxious bov I'm just looking for somthing rather then nothing at all.

anyways I will take the adviseb from others I will stay recirculated and try alluminum piping to acheive this.thank you all for the input.
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Old 09-14-2022, 09:15 AM   #11
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Quote:
Originally Posted by biasword View Post
fwiw i have blacktop with maf with a ssqv vented to atmosphere and have no issues. between shifts or otherwise
stock sr maf or z32 maf? these z32 mafs are much more sensitive to atmospheric relief then the sr maf.
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Old 09-14-2022, 09:37 AM   #12
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Assuming your harness/ecu still uses a stock pinout and you don't mind going a bit oldschool, you could scoop a used SAFC2 from someone and use the decel air setting to compensate for the atmospheric BOV. I would never recommend it as a tuner, but they can be had for cheap now and I remember it worked well when I used it for this purpose back in the day.
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Old 09-17-2022, 09:40 AM   #13
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Quote:
Originally Posted by Rustys14 View Post
Assuming your harness/ecu still uses a stock pinout and you don't mind going a bit oldschool, you could scoop a used SAFC2 from someone and use the decel air setting to compensate for the atmospheric BOV. I would never recommend it as a tuner, but they can be had for cheap now and I remember it worked well when I used it for this purpose back in the day.
That actually works quite well. It has a specific function for assisting with the transition between ecu fuel tps based cutoff and return to idle conditions which clamps maximum maf voltage to prevent fuel cylinder washing. Its pretty slick how apexi knew about the issue and added this feature to something that they really didnt need to add it to. I used to recommend the SAFC-2 for this issue all the time in the past. But its hard to find one now.
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Old 09-17-2022, 07:46 PM   #14
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Quote:
Originally Posted by spools420a View Post
there are two types of people in here,ones who admit they like bov sounds and others who pretend they dont like the sounds to go along with the herd.

deep down were all gear heads who love these turbo sounds even if we dont admit it.

mine makes zero sound,im not looking for "hey everyone look at me" obnoxious bov I'm just looking for somthing rather then nothing at all.

anyways I will take the adviseb from others I will stay recirculated and try alluminum piping to acheive this.thank you all for the input.
As mentioned, the SSQV is your best bet for some sound and minimal negative effects.

I for one enjoy the rupture of noise when the throttle snaps shut and then the subsequent cacophony of chaos when it snaps back open.
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Old 01-09-2023, 09:11 AM   #15
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I for one enjoy the rupture of noise when the throttle snaps shut and then the subsequent cacophony of chaos when it snaps back open.
oh they all do in here,many just dont want to admit it so they dont seem viewed as ricey.
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Old 01-27-2023, 10:48 AM   #16
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Convert to MAP and you can have all the ricer sounds.
Is this a option for me since i have enthalpy ecu setup to run a z32 maf?

i cant find much on the map conversion can you let me know whats involved or a link? thanks.
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Old 01-27-2023, 10:54 AM   #17
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Originally Posted by Rustys14 View Post
Assuming your harness/ecu still uses a stock pinout and you don't mind going a bit oldschool, you could scoop a used SAFC2 from someone and use the decel air setting to compensate for the atmospheric BOV. I would never recommend it as a tuner, but they can be had for cheap now and I remember it worked well when I used it for this purpose back in the day.
how come you dont recommend this idea of safc2 as a tuner? would you recommend another option say map conversion or running ssqbov to metal intake? so far i think ill try the metal intake with my turbosmart bov and see how that goes,and maybe add another resonator to my exhaust and try to get the exhaust as quiet as possable which will make turbo sounds more obvious.

who makes a quiet 3 inch inlet exhaust tip?
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Old 01-27-2023, 12:35 PM   #18
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airflow converter (AFC) only warps the maf signal which tricks the ECU into thinking the engine is moving less air than it really is, so you can use larger injectors. AFC does not make sense to use without installing large injectors. It has nothing to do with the selected maf as the hard limitation is FUEL based, i.e. installing a larger maf does not increase the flow of the current injectors.

If you tell the ECU that airflow is REDUCED so you can use larger injectors and make more power, you can tune the a/f ratio pretty well, the AFC is a powerful and simple tool for this purposes. However, because the ECU thinks the airflow is REDUCED, it also assumes that the engine Volumetric efficiency (cylinder fill %) Is reduced, and because of that issue, the AFC causes too much ignition timing advance. That is you get more and more timing as the injectors get larger and the power is increasing. That is the opposite of what should happen and so, it can and will blow a motor if you do not understand the relationship of this phenomenon. This is why AFC has a bad rap and why people say the AFC is not really 'tuning' the engine- they are right. The AFC is not a tuning solution. It is like a band-aid half solution so you can drive the vehicle with the wrong injectors for a while. However if you actually understand the limitation of an AFC and have a clear picture of how the engine will react in terms of timing than it is quite a valuable and useful piece of electronic equipment despite it's limitations. For example if I am strictly drag racing and don't care about fuel economy I could reduce the timing at the CAS significantly which will ruin my economy and engine efficiency possibly causing carbon buildup and other issues... but it would run really well at WOT with the correctly dialed timing now that I've accounted for the SAFC limitation and I can drag race all day without blowing the engine. Another example is a rom tune which has been properly tuned for larger injectors and has been timed properly as well, the AFC could be used to make minor adjustments without influence the timing too much because we started out very close to the originally properly tuned values and only small corrections are needed. The AFC has it's place just not in most peoples hands.
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Old 01-27-2023, 03:37 PM   #19
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Originally Posted by spools420a View Post
Is this a option for me since i have enthalpy ecu setup to run a z32 maf?

i cant find much on the map conversion can you let me know whats involved or a link? thanks.
You would have to switch ECUs as I do not think Enthalpy supports Map. Look at Link G4
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Old 01-27-2023, 04:11 PM   #20
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how come you dont recommend this idea of safc2 as a tuner? would you recommend another option say map conversion or running ssqbov to metal intake? so far i think ill try the metal intake with my turbosmart bov and see how that goes,and maybe add another resonator to my exhaust and try to get the exhaust as quiet as possable which will make turbo sounds more obvious.

who makes a quiet 3 inch inlet exhaust tip?
I don't recommend piggyback units like the SAFC for tuning since there is not direct timing control. They're fine for small adjustments, but they can be dangerous in the wrong hands and don't stack up well against more modern tuning solutions.

A SAFC2 is perfect for your situation though. The decel air settings are separate from the tuning functions in the unit so you could install one in tandem with your enthalpy ecu and just use the decel air settings to run an atmospheric BOV without having to "tune" anything. It also has a few other useful functions/gauges that are fun to play with, I just recommend leaving the fuel tables alone.

A map conversion would require a standalone ecu which isn't worth the expense if all your looking to do is to run an atmospheric BOV without stalling. An SAFC will get you there for the least amount of money.
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