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Old 12-09-2020, 09:57 PM   #1
ben_7
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Default COBB LE BPV vs COBB XLE BPV vs stock BPV

Hi everyone,

I'm getting my 2020 STi tuned shortly with mostly COBB stage 1+ mods plus a few more preventative mods (with the boost increased to around 18psi).

I really want the "whoosh" sound of the turbo and the "psshh" sound as the air is released.

I understand with my COBB SF intake (with the COBB Airbox), I can hear that quite well, however I've heard that the COBB BPV will make it louder and has a distinctive turbo flutter sound, even though I'm going to be setting it to 100% recirculation.

So my question is does anyone have either of the COBB BPV's and is it louder than the stock BPV when equipped with the COBB SF intake?

Also, is the COBB LE BPV louder than the COBB XLE BPV and which one would be better?

I'm just looking for the loudest turbo sounds since this won't have any performance gain.
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Old 12-09-2020, 10:03 PM   #2
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i had the xle on my 2011 wrx and it sounded the same as stock to me with the cobb intake. only difference is that the cobb will hold more boost and not leak
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Old 12-09-2020, 10:08 PM   #3
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Originally Posted by Haevn View Post
i had the xle on my 2011 wrx and it sounded the same as stock to me with the cobb intake. only difference is that the cobb will hold more boost and not leak
Thanks, yeah for me it's just the sound I'm looking for on my STi. I want a louder, more distinct turbo flutter noise. But if the sound is the same as stock, I'll hold off on buying the COBB BPV.
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Old 12-10-2020, 10:19 AM   #4
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I have the Forge BPV, it made all of those sexy sounds and holds boost all the way up to redline. Also it comes with 3 pressure springs that you can change out.
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Old 12-13-2020, 11:46 PM   #5
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Originally Posted by BlackFighter View Post
I have the Forge BPV, it made all of those sexy sounds and holds boost all the way up to redline. Also it comes with 3 pressure springs that you can change out.


Yeah Iíve heard good things about Forge BPVís on STiís, but I ended up going with the COBB LF BPV.
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Old 12-14-2020, 08:31 AM   #6
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I just ordered a Cobb LF bpv to replace my leaking turbosmart valve. I guess ill update once i have it on the car.
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Old 12-15-2020, 03:50 AM   #7
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Originally Posted by Jay11STI View Post
I just ordered a Cobb LF bpv to replace my leaking turbosmart valve. I guess ill update once i have it on the car.


Cool, please let me know how loud it sounds with it set to 100% recirculating.

Also, do you have an intake installed to amplify the sound?
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Old 12-16-2020, 04:09 PM   #8
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Quote:
Originally Posted by ben_7 View Post
Cool, please let me know how loud it sounds with it set to 100% recirculating.

Also, do you have an intake installed to amplify the sound?
I have an AEM CAI. Unfortunately alot of places are out of the cobb bpv so im going to have to wait 2 - 4 weeks before mine arrives.
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Old 12-16-2020, 04:16 PM   #9
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Originally Posted by Jay11STI View Post
I have an AEM CAI. Unfortunately alot of places are out of the cobb bpv so im going to have to wait 2 - 4 weeks before mine arrives.


Yeah, Iím trying to get one as well. Problem is I might already have the car tuned by then.

Do you need a re-tune if youíre just swapping a fully recirculating BPV with the stock one?
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Old 12-16-2020, 04:49 PM   #10
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I had to rebuild my Cobb LF bpv because they updated the springs and seals. They provided me the kit free of cost but it wasn't exactly reassuring to have to rebuild a brand new part a few months after install. Only way I found out about this was by perusing Cobb's website. No issues yet
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Old 12-17-2020, 12:15 AM   #11
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Default COBB LE BPV vs COBB XLE BPV vs stock BPV

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Originally Posted by standardtranny View Post
I had to rebuild my Cobb LF bpv because they updated the springs and seals. They provided me the kit free of cost but it wasn't exactly reassuring to have to rebuild a brand new part a few months after install. Only way I found out about this was by perusing Cobb's website. No issues yet


Thatís not comforting to know that it had to be rebuilt early on.

I thought the COBB LE BPV was an improvement over the COBB XLE BPV and I went with COBB because they usually make good quality parts.

Hopefully mine comes wit the updated springs and seals.

Sorry to hear that you had to rebuild it, but at least they provided the kit free of cost.

Last edited by ben_7; 12-17-2020 at 02:07 AM.
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Old 12-17-2020, 02:06 AM   #12
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Just asking this question again, do you need a tune if you replace the stock STi BPV with an aftermarket BPV but set to 100% recirculation?
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Old 12-17-2020, 10:21 AM   #13
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As long as it has the same spring rate, no need for a retune for a recirculation setup.
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Old 12-17-2020, 10:32 AM   #14
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Quote:
Originally Posted by BlackFighter View Post
As long as it has the same spring rate, no need for a retune for a recirculation setup.
and assuming there's no leaks from a botched install
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Old 12-17-2020, 11:08 PM   #15
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Quote:
Originally Posted by ben_7 View Post
Just asking this question again, do you need a tune if you replace the stock STi BPV with an aftermarket BPV but set to 100% recirculation?
You have done zero research on this topic. You will have issues and you aren't informed enough now to know what they are and the causes and the preventative maintenance associated with this modification. You need to circle back and start researching or get rid of this idea. This goes for all car modifications.
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Old 12-17-2020, 11:31 PM   #16
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Originally Posted by BlackFighter View Post
As long as it has the same spring rate, no need for a retune for a recirculation setup.


Makes sense, thanks for the reply!
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Old 12-17-2020, 11:31 PM   #17
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Originally Posted by standardtranny View Post
and assuming there's no leaks from a botched install


Makes sense, thanks for the reply!
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Old 12-17-2020, 11:38 PM   #18
ben_7
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Default COBB LE BPV vs COBB XLE BPV vs stock BPV

Quote:
Originally Posted by Unabomber View Post
You have done zero research on this topic. You will have issues and you aren't informed enough now to know what they are and the causes and the preventative maintenance associated with this modification. You need to circle back and start researching or get rid of this idea. This goes for all car modifications.


Actually I have done some research, and I believe I wonít have any issues because this is a simple install and lots of people have installed it.

Which is why I started this thread, in order to initiate a helpful discussion around these BPVís and the install process for anyone (including myself) interested in installing these BPVís.

While Iím not a Subaru expert, I do know that these cars run bad with BOVís which is why I purchased a fully recirculated BPV with a COBB SF intake for the sound I desired.

The reason I post on these forums is to get other ownerís experiences regarding the topic which an FAQ or article doesnít provide.

After all, thatís why we have forums donít we? Isnít this forum a place for Subaru enthusiasts to discuss topics on the cars they love?

But when there are posts like the post you sent me, it actually makes someone not want to post and not use forums at all.

For everyone who posted helpful responses, thank you!

Last edited by ben_7; 12-17-2020 at 11:54 PM.
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Old 01-09-2021, 10:34 AM   #19
Jay11STI
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Ok guys so i finally got my Cobb LF bpv this week and installed it last night. Compared to my turbosmart 50/50 bov on full recirc, the Cobb bpv is louder in my opinion. Its definetly more active so to speak.

Its very possible that my turbosmart valve was just old worn and busted after all these years. None the less i am happy with the Cobb LF bpv.

Last edited by Jay11STI; 01-09-2021 at 11:30 AM.
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Old 01-09-2021, 11:28 PM   #20
ben_7
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Default COBB LE BPV vs COBB XLE BPV vs stock BPV

Quote:
Originally Posted by Jay11STI View Post
Ok guys so i finally got my Cobb LF bpv this week and installed it last night. Compared to my turbosmart 50/50 bov on full recirc, the Cobb bpv is louder in my opinion. Its definetly more active so to speak.

Its very possible that my turbosmart valve was just old worn and busted after all these years. None the less i am happy with the Cobb LF bpv.


I just got my STi pro-tuned with my COBB LF BPV and paired with my COBB SF Intake, itís loud and it sounds great!
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Old 01-10-2021, 02:04 PM   #21
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Quote:
Originally Posted by Jay11STI View Post
I just ordered a Cobb LF bpv to replace my leaking turbosmart valve. I guess ill update once i have it on the car.
Where was your Turbosmart leaking from? Was it the Kompact Plumb Back?

Edit: Nevermind, just read to the bottom and see that you were using a different model.
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