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Old 05-16-2020, 04:40 AM   #1
ben_7
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Default Is getting a pro tune for a BOV safe?

I’m thinking of getting a bunch of mods done to my 2020 STi, and since I really love the turbo noises, I asked the potential tuner about an aftermarket BPV instead of a BOV.

He responded by telling me that a BOV is safe as long as there is a tune for it, thereby telling the engine that it will get either 50% or no air recirculated (depending on vent-to-air percentage).

I understand that with the COBB SF intake I’m planning on getting installed, I would be able to hear the turbo noises, but having a BOV installed is that much better noise-wise.

So my question is, if there is a tune for it, is a BOV safe?
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Old 05-16-2020, 05:59 AM   #2
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Old 05-16-2020, 09:43 AM   #3
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There is no real specific tune for a bov or bpv. The cobb intake will make plenty of turbo noises if thats what your looking for.

I think if you're going to protune the car then having the bov is ok as long as you have it set to recirculate and not vent to atmosphere. The tuner should be able to correct any issues the bov may or maynot create.
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Old 05-17-2020, 04:09 AM   #4
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A tune for a BOV doesn't do that much, with out it your car will run rich for about 1 second during shifts or a fast throttle lift. After that the ecu goes into overrun and cuts fuel anyway, until it hits about 1200rpm or you get back on the gas. But many people take off their bov's in a month after they get tired of the noise. A good intake will make a good noise also.
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Old 05-17-2020, 04:13 AM   #5
ben_7
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Thanks for the link, however I keep reading on the internet and hearing from some people that it’s not good to get a BOV, but some say it’s fine as long as you tune for it.

My question is, on a stock engine, the ECU is setup to expect air back on a full recirculating process. If you tune that out in a pro tune, then will it harm the engine if the ECU is not expecting any air back?

Does the engine still need the recirculated air or can it function without any issues with no recirculated air if it’s tuned out and the ECU does not expect any air back (since the air would have been vented out with a BOV)?
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Old 05-17-2020, 07:45 AM   #6
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Quote:
Originally Posted by ben_7 View Post
I’m thinking of getting a bunch of mods done to my 2020 STi, and since I really love the turbo noises, I asked the potential tuner about an aftermarket BPV instead of a BOV.

He responded by telling me that a BOV is safe as long as there is a tune for it, thereby telling the engine that it will get either 50% or no air recirculated (depending on vent-to-air percentage).

I understand that with the COBB SF intake I’m planning on getting installed, I would be able to hear the turbo noises, but having a BOV installed is that much better noise-wise.

So my question is, if there is a tune for it, is a BOV safe?
Now look son' , just leav'er alone and don't bother' with the fart'n valve. You're gonna muck' things up, this aint' fast n furious, it's not year 2004. You'll be hearin' fartin' noises down the road all day long, it gets' old trust an old dude that's been down that road before, but some follk's gotta learn the hard way. I wish I had a father figure' to tell me what's what, and teach me the ways of life...now pay attention son these are valuable bread crumbs I'm feedin' ya!

You got a lady friend? If ya do, you'll lose some points with yer fart valve and constant turbinin' noises. You wear a flat brim?

Leave that car alone son. Yer not racin' Johnny Tran for pinks at race wars tomorrow, capeesh?
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Old 05-17-2020, 02:09 PM   #7
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Originally Posted by Jacky Treehorn View Post
Now look son' , just leav'er alone and don't bother' with the fart'n valve. You're gonna muck' things up, this aint' fast n furious, it's not year 2004. You'll be hearin' fartin' noises down the road all day long, it gets' old trust an old dude that's been down that road before, but some follk's gotta learn the hard way. I wish I had a father figure' to tell me what's what, and teach me the ways of life...now pay attention son these are valuable bread crumbs I'm feedin' ya!



You got a lady friend? If ya do, you'll lose some points with yer fart valve and constant turbinin' noises. You wear a flat brim?



Leave that car alone son. Yer not racin' Johnny Tran for pinks at race wars tomorrow, capeesh?


LOL, thanks for the post.

Call it personal preference, but I love the whoosh sounds of the turbo. One of the reasons I bought a turbo car.

In any case, I might just go with the COBB BPV, but I’m going to think about a Greddy BOV a little more before going with a BPV.
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Old 05-17-2020, 03:27 PM   #8
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Originally Posted by ben_7 View Post
LOL, thanks for the post.

Call it personal preference, but I love the whoosh sounds of the turbo. One of the reasons I bought a turbo car.

In any case, I might just go with the COBB BPV, but I’m going to think about a Greddy BOV a little more before going with a BPV.
I have an AEM cold air intake on my car for the last several years and I have yet to grow tired from it. In fact, most of the time I purposely make the turbo spool up a bit, just to hear the BPV. If you have the stock intake, look to see if you can remove the silencer, otherwise you may not be able to hear Cobb's BPV either. Edit: just remembered you're getting an SF Intake. Are you planning of flashing Cobb's tune to the car? I hope you understand that the dealership will likely give you flack for being tuned under warranty.

As for the lady friend, just gotta find one that gets just as excited about car parts. There's plenty of fish out there and catch-and-release exists for a reason. This is advice I got a long time ago...from an old lady no less. Basically told me to shop around (not sleep around, there's a difference. You can get to know a person without spinning your rod bearings). If she complains about your car, time to thank the salesman for his time and keep looking..

Anyways...this is the wrong forum for relationship advice...
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Old 05-17-2020, 04:03 PM   #9
ben_7
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Originally Posted by viper_crazy View Post
I have an AEM cold air intake on my car for the last several years and I have yet to grow tired from it. In fact, most of the time I purposely make the turbo spool up a bit, just to hear the BPV. If you have the stock intake, look to see if you can remove the silencer, otherwise you may not be able to hear Cobb's BPV either. Edit: just remembered you're getting an SF Intake. Are you planning of flashing Cobb's tune to the car? I hope you understand that the dealership will likely give you flack for being tuned under warranty.

As for the lady friend, just gotta find one that gets just as excited about car parts. There's plenty of fish out there and catch-and-release exists for a reason. This is advice I got a long time ago...from an old lady no less. Basically told me to shop around (not sleep around, there's a difference. You can get to know a person without spinning your rod bearings). If she complains about your car, time to thank the salesman for his time and keep looking..

Anyways...this is the wrong forum for relationship advice...

Hey thanks for the post. I agree about the turbo noises. I’m sure it will never get old which is one of the main reasons for my STi purchase (an old school turbo with lag).

My STi is stock except for a Nameless axle-back exhaust with 4” tips and 4” mufflers (the boxer rumble sounds so good with this setup), but I am thinking about doing full bolt-on upgrades and getting it pro-tuned all at once.

This will probably void certain parts of my warranty so I’m still thinking if I should do it a bit later since my STi has very low miles.

In any case I’m trying to make about 330 whp and similar wheel torque figures, and I really want to hear the turbo noises as well, so I’m thinking of doing the following mods:

- COBB Stage 3 Flex Fuel kit minus the COBB exhaust, since I’m keeping my Nameless axle back and getting a Nameless mid-pipe to connect to the COBB down-pipe.
- The COBB Stage 3 Flex Fuel kit comes with the COBB SF intake, bigger injectors, COBB Accessport, etc...
- COBB boost controller because I want to raise the boost to about 19-20psi on the stock turbo
- IAG AOS
- Tein coilovers for suspension
- Pro tune

With that and the higher boost setup, I’ll need a new BPV, which is why I was thinking about the COBB BPV and with the COBB SF intake, I should be able to hear all the wonderful turbo noises, however I’m really looking at a Greddy BOV which expands on the noise more, because the potential tuner I’m talking to says that he can tune out the need for air recirculation and tell the ECU to not expect any air back in.

However I’m still concerned about reliability because the MAF is still reading the larger amount of air coming in. And even though the ECU knows to not expect this air back into the engine, the car was initially setup for recirculated air, so would I be harming engine reliability?
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Old 05-17-2020, 09:59 PM   #10
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For what it's worth, and this is just another perspective, not one to dismiss your wants...I have the Cobb Stage 3 + Flex Fuel (AWE Track Catback) with stock BPV (GS EBCS) and you can easily hear all the airbox noises and whooshes with even moderate pedal input and acceleration. My dyno sheets (in Shootout Mode) put my car at 331WHP at 5250RPM and 384 Lb/Ft at 3500RPM (on 93....E60-85 was 362AWHP/446Ft/Lb)

So, if for any reason you're worried about an issue with a tune and BOV or aftermarket BPV, you'll still get lots of noise with the stock one and the mods you want.

Anyway, cheers and enjoy the mod journey ***128522; sorry for my lack of any real input ***128517;

Last edited by DoomAtom; 05-17-2020 at 10:21 PM.
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Old 05-18-2020, 02:59 PM   #11
Jacky Treehorn
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Quote:
Originally Posted by ben_7 View Post
Hey thanks for the post. I agree about the turbo noises. I’m sure it will never get old which is one of the main reasons for my STi purchase (an old school turbo with lag).

My STi is stock except for a Nameless axle-back exhaust with 4” tips and 4” mufflers (the boxer rumble sounds so good with this setup), but I am thinking about doing full bolt-on upgrades and getting it pro-tuned all at once.

This will probably void certain parts of my warranty so I’m still thinking if I should do it a bit later since my STi has very low miles.

In any case I’m trying to make about 330 whp and similar wheel torque figures, and I really want to hear the turbo noises as well, so I’m thinking of doing the following mods:

- COBB Stage 3 Flex Fuel kit minus the COBB exhaust, since I’m keeping my Nameless axle back and getting a Nameless mid-pipe to connect to the COBB down-pipe.
- The COBB Stage 3 Flex Fuel kit comes with the COBB SF intake, bigger injectors, COBB Accessport, etc...
- COBB boost controller because I want to raise the boost to about 19-20psi on the stock turbo
- IAG AOS
- Tein coilovers for suspension
- Pro tune

With that and the higher boost setup, I’ll need a new BPV, which is why I was thinking about the COBB BPV and with the COBB SF intake, I should be able to hear all the wonderful turbo noises, however I’m really looking at a Greddy BOV which expands on the noise more, because the potential tuner I’m talking to says that he can tune out the need for air recirculation and tell the ECU to not expect any air back in.

However I’m still concerned about reliability because the MAF is still reading the larger amount of air coming in. And even though the ECU knows to not expect this air back into the engine, the car was initially setup for recirculated air, so would I be harming engine reliability?
Have it ur way son, I'm just joshin' ya , tuggin' at the ol' yonson as they say! I got some experience in the bisness and I've made my livin' off smellin' the stink if ya know what i mean.

But look here son, I see the writin' on the wall already before the poo even has a chance to dry on this one! You young bucks and ur fart cans. I tell you what, I appreciate ur persistence on this one, I hope it goes well for ya at the end of the day, and you took my ribbin' like a champ!
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Old 05-18-2020, 05:42 PM   #12
ben_7
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Originally Posted by DoomAtom View Post
For what it's worth, and this is just another perspective, not one to dismiss your wants...I have the Cobb Stage 3 + Flex Fuel (AWE Track Catback) with stock BPV (GS EBCS) and you can easily hear all the airbox noises and whooshes with even moderate pedal input and acceleration. My dyno sheets (in Shootout Mode) put my car at 331WHP at 5250RPM and 384 Lb/Ft at 3500RPM (on 93....E60-85 was 362AWHP/446Ft/Lb)



So, if for any reason you're worried about an issue with a tune and BOV or aftermarket BPV, you'll still get lots of noise with the stock one and the mods you want.



Anyway, cheers and enjoy the mod journey sorry for my lack of any real input


Thanks for the reply!

Yeah I think I’ll go with the COBB BPV since I want to raise boost level to 19-20psi on the stock turbo.

Those numbers are really good, what year is your STi?

Also what’s the boost level that you’re running?
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Old 05-18-2020, 06:05 PM   #13
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Made in error - please delete

Last edited by DoomAtom; 05-18-2020 at 06:10 PM.
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Old 05-18-2020, 06:07 PM   #14
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Originally Posted by ben_7 View Post
Thanks for the reply!

Yeah I think I’ll go with the COBB BPV since I want to raise boost level to 19-20psi on the stock turbo.

Those numbers are really good, what year is your STi?

Also what’s the boost level that you’re running?
I have a 2019 STI.

Max Boost: 20 PSI for 93 Tune and 22 PSI for E60-85 Tune

I asked for those Boost numbers to keep the efficiency of the stock turbo in mind. The shop and tuner only suggested the EBCS and said nothing about the BPV. They felt that 22 PSI on Ethanol was within the stock BPV capability.

Last edited by DoomAtom; 05-18-2020 at 06:12 PM.
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Old 05-18-2020, 07:43 PM   #15
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Originally Posted by DoomAtom View Post
I have a 2019 STI.



Max Boost: 20 PSI for 93 Tune and 22 PSI for E60-85 Tune



I asked for those Boost numbers to keep the efficiency of the stock turbo in mind. The shop and tuner only suggested the EBCS and said nothing about the BPV. They felt that 22 PSI on Ethanol was within the stock BPV capability.


That’s cool, I was thinking to do 22psi but then was wondering about the limits of the stock turbo.

How has the setup been for you reliability wise?
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Old 05-18-2020, 08:12 PM   #16
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Originally Posted by ben_7 View Post
That’s cool, I was thinking to do 22psi but then was wondering about the limits of the stock turbo.

How has the setup been for you reliability wise?
I was advised that 22 PSI is the limit before it runs out of breath.

It's been great. The power is completely streetable, and won't come on fully unless I really mash the pedal. I had the COBB Stage 2 OTS prior to the current above mentioned setup and, even without going into boost, I feel like the current setup makes more power. It has the noise from the intake, I can hear the stock BPV, and the exhaust is plenty for my liking ( living in the city, it roars between the buildings). Its been reliable and I'm happy with it.

If you're looking for more noise, an aftermarket BPV/BOV might be to your liking and you'll have a good power base to flex the noise. Not having mufflers with the AWE Track setup, I don't need anymore noise ***128517;
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Old 05-20-2020, 04:39 PM   #17
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ben,

I have a GFB BOV with an adjustable valve you can turn for BOV noises. when I get tired of it, I can turn it to full recirculation and its quiet. its awesome! I have always loved turbo noises. no CEL either... its good to have options...

https://www.rallysportdirect.com/par...blow-off-valve
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Old 05-25-2020, 09:44 PM   #18
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Quote:
Originally Posted by ben_7 View Post
I’m thinking of getting a bunch of mods done to my 2020 STi, and since I really love the turbo noises, I asked the potential tuner about an aftermarket BPV instead of a BOV.

He responded by telling me that a BOV is safe as long as there is a tune for it, thereby telling the engine that it will get either 50% or no air recirculated (depending on vent-to-air percentage).

I understand that with the COBB SF intake I’m planning on getting installed, I would be able to hear the turbo noises, but having a BOV installed is that much better noise-wise.

So my question is, if there is a tune for it, is a BOV safe?


To run a full vent to atmosphere bov you will need to be tuned for speed density as the maf calculates air coming into the engine before the turbo/ bpv recirculating tube. You can also watch the video on smeedia’s YouTube where he puts a bov on his car with the maf still installed, the car will run like crap and it can cause a lot of knock that could cause ring land failure. Visconti tuning makes a pnp harness for sd
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Old 05-30-2020, 03:18 AM   #19
ben_7
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Originally Posted by Blubarusti View Post
To run a full vent to atmosphere bov you will need to be tuned for speed density as the maf calculates air coming into the engine before the turbo/ bpv recirculating tube. You can also watch the video on smeedia’s YouTube where he puts a bov on his car with the maf still installed, the car will run like crap and it can cause a lot of knock that could cause ring land failure. Visconti tuning makes a pnp harness for sd


Thanks for the reply. Just to be safe I’ll run a COBB BPV and still should be able to hear the turbo noises with the COBB SF intake. And a pro tune as well.
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