Welcome to the North American Subaru Impreza Owners Club Saturday November 22, 2014
Home Forums WikiNASIOC Products Store Modifications Upgrade Garage
NASIOC
Here you can view your subscribed threads, work with private messages and edit your profile and preferences Home Registration is free! Visit the NASIOC Store NASIOC Rules Search Find other members Frequently Asked Questions Calendar Archive NASIOC Upgrade Garage Logout
Go Back   NASIOC > NASIOC Technical > Factory 2.0L Turbo Powertrain (EJ Series Factory 2.0L Turbo)

Welcome to NASIOC - The world's largest online community for Subaru enthusiasts!
Welcome to the NASIOC.com Subaru forum.

You are currently viewing our forum as a guest, which gives you limited access to view most discussions and access our other features. By joining our community, free of charge, you will have access to post topics, communicate privately with other members (PM), respond to polls, upload content and access many other special features. Registration is free, fast and simple, so please join our community today!

If you have any problems with the registration process or your account login, please contact us.
* Registered users of the site do not see these ads.
Reply
 
Thread Tools Display Modes
Old 11-04-2007, 05:43 PM   #176
WeldingHank
Scooby Specialist
 
Member#: 98645
Join Date: Oct 2005
Chapter/Region: NESIC
Location: Lawrence,ma
Vehicle:
2002 WRX Wagon
PSM

Default

did this mod about 8 months ago. Haven't looked back. I do get compressor stall at lower pressures, but above 10-ish psi it dumps hard and fast. I Love that it sounds like a BOV when i'm going flat out at WOT.
* Registered users of the site do not see these ads.
WeldingHank is online now   Reply With Quote
Old 11-05-2007, 03:58 AM   #177
Wrx_Fan_0717
Scooby Specialist
 
Member#: 152080
Join Date: Jun 2007
Chapter/Region: South East
Location: Pensacola, FL
Vehicle:
6266 Precision'd Big
Cam'd 2.55l 6spd Bugeye

Default

Quote:
Originally Posted by ride5000 View Post
dude, i know what surge sounds like. some of us have been playing around with subies for quite some time now.

a little waffle is perfectly fine with me. are you going to tell me that my vf23 is going to die any second now? when it does, can you tell me it was the modded oem bpv, or the fact that i flog 25psi out of it every day? how about the period of time last winter when i was running 27+psi?

crushing the top postpones the inevitable. if you understand the way the bpv is put together, and how it operates, you would know this. this is exactly why dibble only got his up to 28psi. i GUARANTEE you that mine will hold that, and more. i know because i've done it.

ken

ps. since you think surge of any kind is the devil, why don't you tell quirt he's an idiot for selling garrett gt series turbo kits WITHOUT any kind of bpv/bov?
Yea, i reread that i did sound like an ass.
Your putting words in my mouth though.
I know your a Guru but just because my says Specialist doesn't mean i don't know how a BPV works.

Hey all i am saying is i don't prefer to have compressor surge. I like to stay on the cautious side. If it standard protocol with boost is WITHOUT compressor surge, i would like to keep it that way.

So there is a GT kit without a venting system... hey i am sure they have hours/months of designing & engineering into it. Who am i to challenge that? Not touching that one.

But, my personal opinion on my own VF34 and my Blouch 20g i would rather not here surge every shift. Well i am still not as brave as you running 27psi either. I guess it comes down to what your comfortable with.

I need my 2.0 block to last until after the PPGs. Then i'll boost it until it pukes on itself. Then 2.5 it is.

Last edited by Wrx_Fan_0717; 11-05-2007 at 04:11 AM.
Wrx_Fan_0717 is offline   Reply With Quote
Old 11-05-2007, 07:19 AM   #178
ride5000
Scooby Guru
 
Member#: 32792
Join Date: Feb 2003
Chapter/Region: NESIC
Location: lincoln, ri
Vehicle:
2003 GGA MBP
12.9 / 105+

Default

Quote:
Originally Posted by Wrx_Fan_0717 View Post
I know your a Guru but just because my says Specialist doesn't mean i don't know how a BPV works.
i could care less what someone's title says.

i base my assessment of someone's knowledge on how thoroughly they understand the aspects of the situation under discussion.

crushing the top will only increase the spring preload. it does not change the proportion of pneumatic signal pressures applied to the "open" and "close" sides of the diaphragm--that is purely a matter of surface area.

the oem valve uses pre-tb pressure to OPEN the valve via the diaphragm. it is unlike every other aftermarket bov/bpv in this respect. that is why that little port on the IC flange is there in the first place... to route the pre-tb pressure to the "open" side of the diaphragm. this "open" force is in addition to the inherent pressure applied directly to the poppet valve itself, pushing it off its seat. almost every other bpv/bov has this "open" force (there is one that opens against source pressure, IIRC), but none of them have the additional pressure source routed to the diaphragm in opposition to that applied by the post-tb signal line.
ride5000 is offline   Reply With Quote
Old 11-11-2007, 12:28 PM   #179
BurschiK
Scooby Newbie
 
Member#: 109250
Join Date: Mar 2006
Default

Quote:
Originally Posted by BurschiK View Post
First of all, please excuse my bad english, I'm coming from Austria
This is what I don't unterstand. After your mod you have the boost pushing against the valve, on the other side of the valve you have atmospheric pressure plus the spring load
Ok ok, my fault was to think that the hole goes to the backside of the diaphragm
I did this mod now too, but I wasn't happy with the hole getting unfiltered air into the BOV. So I did the Mod this way:

I love that PFZISCHHHHH at shifting
BurschiK is offline   Reply With Quote
Old 11-11-2007, 08:21 PM   #180
martinus
Scooby Newbie
 
Member#: 133233
Join Date: Nov 2006
Location: In muddy corn fields
Vehicle:
Your avg. 3300lb
Winter DD/GG.

Default

So... if I whack the center of the STOCK BP Valve cap, witha ball pin hammer. To produece a 3mm deep indentaion, on the cap ...

Will that get the cool chipmunk sound @ partial STOCK boost, but the whoosh/whistle @ peak STOCK boost ?

martinus is offline   Reply With Quote
Old 01-26-2008, 01:49 AM   #181
tex_wrex
Scooby Newbie
 
Member#: 132971
Join Date: Nov 2006
Chapter/Region: TXIC
Location: Bryan, TX
Vehicle:
2011 STI
DGM

Default

wow this thread is old....

so whats the verdict? is the amount of surge from the .16 mod enough to ruin the turbo? i plan on going 18g very soon..

am i correct in saying that crushing it will allow it to hold higher than stock (i.e. 20-22ish?) boost without the surge problem?
tex_wrex is offline   Reply With Quote
Old 01-26-2008, 06:45 AM   #182
Crazykev
Scooby Specialist
 
Member#: 93667
Join Date: Aug 2005
Chapter/Region: MWSOC
Location: Cincinnati,Oh
Vehicle:
'03 Build'n a 2.12L
331whp/331wtq

Default

Not modded stock BPV will hold 23 psi no problem. At least mine does
Crazykev is offline   Reply With Quote
Old 01-26-2008, 07:57 AM   #183
ride5000
Scooby Guru
 
Member#: 32792
Join Date: Feb 2003
Chapter/Region: NESIC
Location: lincoln, ri
Vehicle:
2003 GGA MBP
12.9 / 105+

Default

my modded stock BPV will hold 27psi no problem. at least mine does..

turbo (vf23) is running fine. last time i had the DP off a few weeks ago there was no shaft play.
ride5000 is offline   Reply With Quote
Old 01-26-2008, 11:29 AM   #184
Crazykev
Scooby Specialist
 
Member#: 93667
Join Date: Aug 2005
Chapter/Region: MWSOC
Location: Cincinnati,Oh
Vehicle:
'03 Build'n a 2.12L
331whp/331wtq

Default

Ride, I've been thinking aout doing this mod, but the factory one works fine from what I can tell.

Kinda' cool that if the stock BPV is open at an idle, then the air is totally bypassing the turbo and my entire FMIC pipework. Will it still do that if it is modded?
Crazykev is offline   Reply With Quote
Old 01-28-2008, 07:59 PM   #185
tex_wrex
Scooby Newbie
 
Member#: 132971
Join Date: Nov 2006
Chapter/Region: TXIC
Location: Bryan, TX
Vehicle:
2011 STI
DGM

Default

also, does the crushed method still have the surge problem? im trying to decide which way to go. i dont want to show up to the tuner and have to fix something last minute to hit the boost i wanna run...
tex_wrex is offline   Reply With Quote
Old 01-28-2008, 08:08 PM   #186
WeldingHank
Scooby Specialist
 
Member#: 98645
Join Date: Oct 2005
Chapter/Region: NESIC
Location: Lawrence,ma
Vehicle:
2002 WRX Wagon
PSM

Default

your either surging or leaking, pick one.
WeldingHank is online now   Reply With Quote
Old 03-15-2008, 01:23 AM   #187
caracer22
Scooby Specialist
 
Member#: 171076
Join Date: Feb 2008
Chapter/Region: SCIC
Location: Lancaster, CA.
Vehicle:
2011 Wrx DGM
STG 2

Default

so i did the mod minus drilling the whole in the side...before plugging the hole to the bpv and having the recirc hose removed and plugged the stock bpv would leak at idle car would stall ect... now with this mod done i just figured i would check and to my suprise no more leak at idle... took the car around the block car runs fine. now other than the usual rich condition between shifts that will be induced will this hurt anything by runing like this and by not drilling the second vent hole hurt the BPV?

Flame On i know it will happen
caracer22 is offline   Reply With Quote
Old 03-21-2008, 12:57 AM   #188
03WRX-WRB
Scooby Specialist
 
Member#: 167879
Join Date: Dec 2007
Chapter/Region: South East
Location: Lancaster, sc
Vehicle:
2005 Impreza
midnight blue

Default

well how much surge are we talking here? nothing more than fully Atmosphere BOV so then why are people complaining...i think most/every aftermarket bov is going to give you compressor surge so if this gives you a little it shouldnt be a big deal,

i just did the mod and am waiting to try it out need my tranny in first
03WRX-WRB is offline   Reply With Quote
Old 03-21-2008, 07:15 AM   #189
TheMadScientist
Scooby Guru
 
Member#: 23717
Join Date: Aug 2002
Chapter/Region: NESIC
Location: Beverly, MA
Vehicle:
2005 Big red

Default

Quote:
Originally Posted by 03WRX-WRB View Post
well how much surge are we talking here? nothing more than fully Atmosphere BOV so then why are people complaining...i think most/every aftermarket bov is going to give you compressor surge so if this gives you a little it shouldnt be a big deal,

i just did the mod and am waiting to try it out need my tranny in first

I have ~50k miles on a 20G using this mod. The "surge" is very minor. I have not had any decrease in performance from the turbo, next time I have it off the car(do't know when that will be) I will take some pics of the compressor. My guess is there is no damage from the light surge.
TheMadScientist is offline   Reply With Quote
Old 04-25-2008, 11:53 AM   #190
newbluwrx
Scooby Newbie
 
Member#: 178397
Join Date: Apr 2008
Default

Quote:
Originally Posted by PaulRex View Post
I crushed my stock BOV, old DSM thing.. sounds alittle simpler than what you did.
how did you crush it? im lookin to do the same to mine but no sure exactly how to
newbluwrx is offline   Reply With Quote
Old 06-18-2008, 01:03 PM   #191
SeeeeeYa
NASIOC Supporter
 
Member#: 129681
Join Date: Oct 2006
Chapter/Region: MAIC
Location: WV
Vehicle:
2015 WRX Ltd CVT
GBP

Default

Quote:
Originally Posted by TheMadScientist View Post
I have ~50k miles on a 20G using this mod. The "surge" is very minor. I have not had any decrease in performance from the turbo, next time I have it off the car(do't know when that will be) I will take some pics of the compressor. My guess is there is no damage from the light surge.
I can't thank you enough for this mod. After my AVO380 install I got my boost tuned perfectly, or so I thought. But as time went on the logging data suggested otherwise. I've got all the other mods, but for some strange reason the LGT community doesn't like to talk about BOV/BPVs, so I kept the stock BPV out of ignorance I guess.

A friend mentioned that he'd used the "crush mod" and my searching turned up this thread. Since our stock BPVs are plastic there would be no crush mods on it, but the $0.16 BOV mod sounded better anyway. I did it a few days ago and am amazed. It is clear my stock BPV was leaking and I had tuned around it, as best one can. Now that I've gotten my WGDC tables to account for the modded BPV I have quicker spool and more power, all from the same 22.5psi I've always chosen. I may change that now .

The light compressor surge I initially got with a quick throttle lift has largely disappeared after tuning my WGDC, AND learning to drive without snapping the throttle shut. Combined with your calming reassurance and length of experience with this modification I have no worries at all. Plus, I just saved hundreds of dollars.. WoW.
SeeeeeYa is online now   Reply With Quote
Old 06-18-2008, 03:01 PM   #192
paintbing
Scooby Specialist
 
Member#: 59388
Join Date: Apr 2004
Chapter/Region: RMIC
Location: Utah --> Monterey, CA
Vehicle:
2003 WRX - Hybrid
I do my own stunts

Default

I have this mod as well. VERY GOOD!
paintbing is offline   Reply With Quote
Old 07-05-2008, 11:48 PM   #193
hybrid gti 2
Scooby Guru
 
Member#: 67004
Join Date: Jul 2004
Chapter/Region: SCIC
Location: (818) 200k+ ej205 ppg 5mt
Vehicle:
02 vf30 pnp wagon
silver and cf

Default

After reading 8 pages of this I really quesion what I should do. I want more boost from my vf30 setup. As I have heard of some people getting 23 psi from a vf34. So wondering how I can do the same.
hybrid gti 2 is offline   Reply With Quote
Old 07-07-2008, 07:35 AM   #194
ride5000
Scooby Guru
 
Member#: 32792
Join Date: Feb 2003
Chapter/Region: NESIC
Location: lincoln, ri
Vehicle:
2003 GGA MBP
12.9 / 105+

Default

a vf dirtywhore will make 23 psi pretty easily. the question is, will your tune handle it?
ride5000 is offline   Reply With Quote
Old 08-06-2008, 02:51 PM   #195
thewerxracing
Scooby Specialist
 
Member#: 141498
Join Date: Feb 2007
Chapter/Region: Tri-State
Default

Okay, Well I dont wanna start a new thread with this one going so Ill just ask here.

Im running this setup:

TD04
HKS TBE
Inlet,Y-Pipe
Bigger TMIC
TiAl 38 EWG

I went from the TXS RFL BOV to a Stock BPV. The car ran normal, quick as usual, just quieter as a Stock BPV is.

I decided to do the mod. I put in the set screw, drilled the hole, and installed.

Bad:
The car runs like crap now. Bogging, afterfiring, and falling on its face. Another thing is the boost gauge is only reading 10 at WOT. (Down from 20).

Good: The EWG sounds like a Rally Car when I let off the throttle (Awesome). And thats the only good thing I can think of.

My boost gauge is reading thru the BOV hose. Could that be causing the reading of 10lbs?
What could be causing the other problems? Can you screw up the mod? Is the BPV bad?


Thanks guys.
thewerxracing is offline   Reply With Quote
Old 08-11-2008, 08:45 AM   #196
Supercharger
Scooby Newbie
 
Member#: 186567
Join Date: Aug 2008
Default

Hi guys.
It's very interesting information but i do not understand it at all.
I have one question to you. maybe someone of you know it.
I have stock MY99 bypass valve.
What mods should i do to have "PSHHHHH" sound while shifting?
Thats photos of my valve:




it have 2 holes, i marked it with red.
thanks a lot.
Supercharger is offline   Reply With Quote
Old 08-11-2008, 09:11 AM   #197
Supercharger
Scooby Newbie
 
Member#: 186567
Join Date: Aug 2008
Default

this hole not deep, it is 5mm.
Supercharger is offline   Reply With Quote
Old 08-12-2008, 08:10 AM   #198
Supercharger
Scooby Newbie
 
Member#: 186567
Join Date: Aug 2008
Default

Supercharger is offline   Reply With Quote
Old 08-12-2008, 02:10 PM   #199
ride5000
Scooby Guru
 
Member#: 32792
Join Date: Feb 2003
Chapter/Region: NESIC
Location: lincoln, ri
Vehicle:
2003 GGA MBP
12.9 / 105+

Default

if you want a psshhh sound, go with a vent to atmosphere (VTA) blow off valve (BOV).

the oem valve is a recirculating bypass valve, and will never be as loud.
ride5000 is offline   Reply With Quote
Old 08-13-2008, 12:44 AM   #200
ProfessorBlinks
Scooby Newbie
 
Member#: 183095
Join Date: Jun 2008
Chapter/Region: NESIC
Location: Upstate NY
Vehicle:
2004 WRX Winter
Blue

Default

Make sure to get a tune if you get a atmosphere BOV!
ProfessorBlinks is offline   Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump


All times are GMT -4. The time now is 11:38 PM.


Powered by vBulletin® Version 3.7.0
Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
Powered by Searchlight © 2014 Axivo Inc.
Copyright ©1999 - 2014, North American Subaru Impreza Owners Club, Inc.