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Old 01-25-2006, 09:43 AM   #126
ride5000
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pic of mine... note the location of the small breather hole:

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Old 02-09-2006, 12:26 PM   #127
Jpizzzle
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So then is this mod only for upgraded turbos or will it help on stockies? just to clearify, you do need the retune after this mod is done, correct?
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Old 02-09-2006, 01:32 PM   #128
cdvma
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It won't help on stockers. You do not need to retune after this mod unless you know for a sure fact that the BOV was leaking at any point under power.
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Old 02-09-2006, 01:35 PM   #129
ride5000
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do you NOT need to retune unless your oem bpv was leaking an insane amount of air during your first custom tune.

it won't hurt a stock turbo. if running 1 bar or less it's not necessary. if running >18psi then i would do it.

jm2c
ken
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Old 02-12-2006, 10:25 PM   #130
gaby
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Quote:
Originally Posted by firebomb
or try this

good bov mod also
My 91 DSM is modded that way. I think I'm going to try it with the Subby.
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Old 02-15-2006, 10:14 AM   #131
TurboRex
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My only concern with this mod is if it can blow off enough air when the throttle body closes when running a large turbo at high boost. I have an fp red and run about 21psi on my sti with pump gas.

Greg
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Old 02-15-2006, 01:42 PM   #132
azarchie
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I machined a billet cap for mine that has an adjustment screw in it. it clamps onto the existing steel cap, and seals with an o-ring. It is currently holding 20 pounds(EJ5-40T), and working just as good as stock.
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Old 09-11-2006, 12:56 PM   #133
p_ilis
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How do I know if I have a STi type of BOV that don't need this mod? Will the whole that should be blocked not exist?

/Peter
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Old 09-22-2006, 05:09 AM   #134
p_ilis
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Did the mod yesterday. If anyone is interested I can post up some pictures.



/Peter
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Old 09-22-2006, 06:04 AM   #135
TheMadScientist
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Quote:
Originally Posted by TurboRex View Post
My only concern with this mod is if it can blow off enough air when the throttle body closes when running a large turbo at high boost. I have an fp red and run about 21psi on my sti with pump gas.

Greg
GT35 @ 28psi no problem.

TMS
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Old 09-22-2006, 10:40 AM   #136
skimobile
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Why havent the moderators made this article and the crush cap mod a sticky yet! With all the constant BOV questions, they should.
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Old 09-22-2006, 12:54 PM   #137
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Quote:
Originally Posted by p_ilis View Post
Did the mod yesterday. If anyone is interested I can post up some pictures.



/Peter
please post pics.

Quote:
Originally Posted by skimobile View Post
Why havent the moderators made this article and the crush cap mod a sticky yet! With all the constant BOV questions, they should.
i agree.
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Old 09-22-2006, 01:40 PM   #138
p_ilis
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Here are two pictures:

The hole that we blocked:


The hole that we drilled (into the same channel that we blocked):


I havn't installed it yet so I can't tell you if it made any difference.

/Peter
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Old 09-22-2006, 01:45 PM   #139
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Quote:
Originally Posted by mmurray75 View Post
OK so I am a cheap sob. I want to run over 18psi on my 16G but the stock BOV opens around that pressure. So what are my options?
1)Buy an atomsphere BOV.
I borrowed one and got really sick of the noise I like stealth.
2)Buy a recirculate BOV.
I am cheap and don't want to spend $200+ on one.
3)The $0.16 mod
Very cheap and stealth this fit the bill perfect. Still 100% recirculate so no idle problems or rich between shift problems. This will allow you to run as much boost as you can throw at it and not open. The one drawback to this that I have found is that around 5-10psi when you shift you will get a real quick real short surge. This will not happen at higher boost levels.

The Mod:
Take off the BOV and look at the face that mounts to the IC. You will see two holes a big one and a small one. The big hole is the valve that releases the pressure the small hole is a boost signal line.
What I did was to take a 1/4-20 tap and drilled out the small hole and tapped it. Be careful to not let any shavings go into the hole. I held the BOV upsid down while drilling and tapping. Then I took a 1/4-20 set screw put teflon tape on it and sealed off that hole.
Then on the body of the BOV you can see where that signal hole goes through the casting. You want to drill in to that signal line and vent it to atmosphere. There is a bung cast into the BOV body to do this.

I have some pics that I will try to post tonight. Any comment or questions?

Mark

I just installed a Forge brand blow off valve that recirculates like stock and car is smoother and less notchy between shifts....they come with different springs to meet your boost needs. My car is stock but moving up to a Cobb ap stg 1. I guarantee that you will like this mod. $150 and it looks bling too. You here the turbo better and has a unique ping sound between shifts.
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Old 09-22-2006, 02:09 PM   #140
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Quote:
Originally Posted by Boosto View Post
I just installed a Forge brand blow off valve that recirculates like stock and car is smoother and less notchy between shifts....they come with different springs to meet your boost needs. My car is stock but moving up to a Cobb ap stg 1. I guarantee that you will like this mod. $150 and it looks bling too. You here the turbo better and has a unique ping sound between shifts.

IMO the $0.16 mod is better than any BOV <$250.
I have used many different ones and they either didn't hold boost or surged the hell out of the turbo.

Ohh and the price went up on the set screws. They are now $0.29.

TMS
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Old 09-22-2006, 04:27 PM   #141
DaFastOne
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how long is the set screw? and what size drill bit did u use to tap the side of the bov?

Last edited by DaFastOne; 09-22-2006 at 05:04 PM.
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Old 09-22-2006, 04:58 PM   #142
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I use a 1/4-20X1/4" set screw. I just use the drill bit for the 1/4-20 tap to drill the hole on the side. You just want to drill in ~1/4" just enought to open the passage. Do not drill out the other side of the passage that you block with the set screw.

TMS
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Old 12-13-2006, 04:33 AM   #143
The Head
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Reviving the thread.
With this mod mine held 28psi on a Frank 50 on the dyno. It works well. It's a bit choppy sounding with the mod on the street for daily driving, but after several months I got used to it and it doesn't affect driveability at all.
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Old 12-13-2006, 09:33 AM   #144
marcymarc
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this is weird. mine holds 21psi perfect with no modification????
maybe its justa freak? ill admit, it shocked me when it first happened
on the dyno, but hey, it works, and no problems over the past
couple months, so yea...
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Old 01-09-2007, 01:06 AM   #145
Trigun001
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My stock turbo (ive been tuned) reached a record high today at 19 psi. while thats cool and stuff i figure as it gets hotter its only going to try to push more boost. If I does do you think Ill need to fix up the stock BPV?
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Old 01-17-2007, 02:39 PM   #146
jhj
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Default $0.16 BOV mod

I modified my OEM BOV as described and I think this is one of the cheapest and best mods yet. It holds boost when shifting so there is no loss of spool up lag that makes shifts mushy. Oh by the way its a 4EAT. Now shifting is like a paddle shift on a Lambo.
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Old 03-03-2007, 09:15 AM   #147
PeteDucati
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jhj - I too have a 4eat and EVERY aftermarket BOV would flutter at low rpm. When I tuned it NOT to flutter it would leak at higher boost pressure. I've been using the JDM STi BPV but my tuner once claimed it was leaking when I had the SZ55 installed - I've since down sized my turbo to the 18g but will be using meth and a 3 bar sensor to jack the boost as high as I can.

Will this mod get my old WRX valve to hold ~30psi (probably push less than that) and still release at very low boost pressures?
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Old 05-06-2007, 03:44 PM   #148
WRX_UA
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I have been running Blitz Dual Drive BOV for a year already. Its atmospheric BOV. Tried to use stock one with NO mods (because I didn't know) DUMPED TO ATMOSPHERE... It occured to be to soft and I had MAJOR idle problems like jumping from 500 to 1600rpm continiously and then the engine stopped completely... . Now, read this thread. Blocked the hole, drilled the new hole, as on the picture shown. Tomorrow i will install and make a write-up about the modded stock WRX BPV. BUT(!) mine will be ATMOSPHERIC, without recirculation, because recirculated BPV DO NOT keep up with FAST SHIFTING. The car jerks, between fast shifts.
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Old 05-06-2007, 04:33 PM   #149
IIdiceII
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being serious^?

learn to drive then
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Old 05-06-2007, 04:51 PM   #150
WRX_UA
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Quote:
Originally Posted by IIdiceII View Post
being serious^?

learn to drive then
Trust me, if you dont have that kind of issue you should learn to drive then
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