Blitz SS BOV SR20 Help

[TheVinylKingz]

I installed a Blitz BOV on my SR20det powered s13. I don?t drift this it?s just a daily driver / project car.

Anyways, ever since I installed the blitz BOV sometimes the motor stalls when going from high boost and coming to a quick stop (shifting to neutral) strange, not sure why. I?ve always had a side-mount with the stock recirculating system.

Also, does anyone know how now much tension the BOV needs?

Picture link as a reference

https://ibb.co/D8BcQtd
https://ibb.co/pRkyrjf

[e1_griego]

It stalls because of the way a maf car works.

The ecu is reading airflow through the maf, and when you vent the bov atmospherically all that air that it metered is let out of the charge piping. The ecu has already compensated for this air by adding fuel, and when the air disappears all that fuel stalls the motor.

You can tighten the spring to the point that the bov is basically stuck shut. Pretty sure the blitz DD came with the recirculation flange, but not sure about the SS.

The complicated and expensive fix is to get a map-based ecu and ditch the maf entirely, but that's a couple thousand dollar fix for a vented bov lol.

[TheVinylKingz]

Originally Posted by e1_griego

It stalls because of the way a maf car works.

The ecu is reading airflow through the maf, and when you vent the bov atmospherically all that air that it metered is let out of the charge piping. The ecu has already compensated for this air by adding fuel, and when the air disappears all that fuel stalls the motor.

You can tighten the spring to the point that the bov is basically stuck shut. Pretty sure the blitz DD came with the recirculation flange, but not sure about the SS.

The complicated and expensive fix is to get a map-based ecu and ditch the maf entirely, but that's a couple thousand dollar fix for a vented bov lol.

Thanks for the reply and providing some sense to this issue. I will tighten the spring and see what happens. If the same problem continues I?ll swap back to the stock recirculating system. Feel weird going backwards.

If I upgrade to an HKS will this still be an issue or is it the type of BOV, ?Blitz BOV?, that is the problem.

[jedi03]

from what I understand its the vent to atmosphere...i ran the same BOV with same issues...didnt seem to have issue with running a TIAL but the tune may have been compensated for it too...

[TheVinylKingz]

Originally Posted by TheVinylKingz

I installed a Blitz BOV on my SR20det powered s13. I don?t drift this it?s just a daily driver / project car.

Anyways, ever since I installed the blitz BOV sometimes the motor stalls when going from high boost and coming to a quick stop (shifting to neutral) strange, not sure why. I?ve always had a side-mount with the stock recirculating system.

Also, does anyone know how now much tension the BOV needs?

Picture link of BOV as a reference.

https://ibb.co/D8BcQtd
https://ibb.co/pRkyrjf

[Thursday7]

It's purely the vent to atmosphere paired with a MAF system. Weld the charge pipe closed and put the Blitz on a shelf. You'll get your fanboy turbo noises and won't lose any metered air. Routing a recirculation is a drag.

[TheVinylKingz]

Originally Posted by Thursday7

It's purely the vent to atmosphere paired with a MAF system. Weld the charge pipe closed and put the Blitz on a shelf. You'll get your fanboy turbo noises and won't lose any metered air. Routing a recirculation is a drag.

So basically the SR20 doesnot need a recirculation system?? I can run it with out a BOV as well? Any issues if I do?

[mav1178]

plenty of answers, any of the responses for a MAF car applies to your situation. up to you what you want to do.

https://www.google.com/search?q=reci...tmospheric+bov

[Thursday7]

Originally Posted by TheVinylKingz

So basically the SR20 doesnot need a recirculation system?? I can run it with out a BOV as well? Any issues if I do?

The BOV is an accessory, not a requisite of function. Theoretically it is a device to extend the turbocharger's longevity. In my eyes, the modern consensus is that running one isn't really necessary. I'd only use one if I wanted to daily my SR and get like 100,000+ miles out of a turbo.

[dorkidori_s13]

SSQV doesnt really have this problem

push type BOVs like the factory unit and your Blitz dont work well vented on stock SR ECU. they need to be recirculated. SR ECU creates a richer state when the throttle body snaps shut and the BOV purges air. ECU is anticipating a rush of air coming back in thru the intake from the BOV. Push types operate off a spring and tend to allow air bleed at lower boost off throttle (which isnt good).

pull type BOVs like HKS SSQV are much less prone to causing the engine to die as they tend to keep more air in the turbo system. been running SSQV 3 since 2011. daily drove my S13 for roughly 4-5 years without recirc. rarely ran into stalling issues. went to a powerFC DJetro (MAP) a few years back, dont have that issue at all anymore.

but yeah, youll need to recirc your BOV to prevent stalling out due to BOV being push type. if you ditch the Blitz you have and go with HKS SSQV, youll find that youll have far fewer issues with bogging/stalling.

[LoSt180]

I've been seeing more and more guys chime in with "a bov isn't needed" in recent years. Just screams drift missile shenanigans to me for guys who blow up their engine every year.

Atmosphere BOV issues have been documented for years on the SR, so plenty of resources for you to search out there. Old threads from 2006 are still relevant because it's not like the mechanics of these engines have changed in 20+ years. Basically as mentioned above, because the MAF has already metered air, the car goes very rich once the BOV dumps the air.

You can still upgrade your BOV and recirculate it. Most either come with, or offer a fitting so you can connect the recirc pipe back into the intake system. I have the HKS SSQV with a fitting recirculated on my S14 and it's been running strong for years now.

[TheVinylKingz]

Thank you for the reply everyone I went ahead and went back to stock recirculation, but the SR keeps on dying. I went ahead and installed a “brand new IACV” that I bought a few years ago, and it continued to display the same symptoms. On high boost going into a hard stop, it looses air and it dies unless I Rev up the motor.

My idle on cold starts is approximately 800-1000 when it settles it’s 700-800

[Kingtal0n]

maf placement issue, maf too close turbo or too close to filter or inadequate straight pipe inline with maf, or maf is dirty, or there is a leak near the maf. Or the recirculation is buffeting the maf hotwire, too close to maf. If the turbo upgraded the volume of air excessive for stock size or location recirculation.

Otherwise, look for dropping fuel pressure and watch wideband. Rich wideband = maf issue. Lean wideband = leaking air or fuel pressure or clogged injectors or something with fuel

[TheVinylKingz]

Originally Posted by Kingtal0n

maf placement issue, maf too close turbo or too close to filter or inadequate straight pipe inline with maf, or maf is dirty, or there is a leak near the maf. Or the recirculation is buffeting the maf hotwire, too close to maf. If the turbo upgraded the volume of air excessive for stock size or location recirculation.

Otherwise, look for dropping fuel pressure and watch wideband. Rich wideband = maf issue. Lean wideband = leaking air or fuel pressure or clogged injectors or something with fuel

Thanks KingTal0n! You been very supportive and helpful! I will look more into the maf. Question Nissan still sells S14 SR20det Mafs. My question is if I keep a stock set up can I use the S14 SR20DET Maf or should I buy a new/refurbished KA24E Maf from Orilley?

Today I did check my ECU and it was giving me a code for MAF and CAS, the CAS is brand new. By default it?s
Got to be the MAF or wiring or maybe a combination or what you mentioned.

[jedi03]

OEM is better...the scaling seems to be off on the rebuilt options...I had to send my maf to martin/enthalpy to get my tune right as I didnt want to spend extra on an oem unit