blow off

That spinning thing that makes all of the cool noises. OE and Aftermarket.

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subyNW
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blow off

Post by subyNW »

so i want to get a hks blowoff.. am i able to release to atmosphere??

and if that isnt a good idea can someone please point me in the right direction lol

(im a noob)
94SS_Canada
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Post by 94SS_Canada »

Blow-Off valve+MAF= Not a good idea.

If your completely stock id stay with the BPV, If your running a crazy build with lots of pressure than maybe you can consider a BLOW-OFF.

If you ever do the TD-04/TMIC conversion then id look at possibly upgrading the BPV, although it is not a neccesity as the Stock BPV is good up to 20psi i believe.

dont mess with a good thing, Stock.
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subyNW
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Post by subyNW »

thank you sir



thats why i love you guys
94SS_Canada
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Post by 94SS_Canada »

You can see alot of guys have run i nice WRX BPV setup with the 04 WRX TMICs and the TD04.
FastRust
Imprezive
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Post by Imprezive »

Blow off Valve + Pull through MAF (like our subi's have) = not such a bad idea.

Blow off Valve + Push through MAF = not really a problem.

Honestly, there are a plethora of people running atmo-venting BOV's on their cars. It doesn't really hurt anything but your ears. You run rich for a millisecond and your car might burp a little backfire every once in a while but nothing detrimental to the engine.

Prove me otherwise?

I will agree that for our cars a recirculation type valve would be best. But I do not see a problem running an atmo-venting unit.
1992 T-Leg = 195whp 197wtq SOLD :(
1988 4Runner RIP
2006 Suzuki DRZ400sm
2007 Miata
1994 Miata
2003 WRX Wagon
2016 Mazda 3
n2x4
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Post by n2x4 »

Imprezive wrote:Blow off Valve + Pull through MAF (like our subi's have) = not such a bad idea.

Blow off Valve + Push through MAF = not really a problem.

Honestly, there are a plethora of people running atmo-venting BOV's on their cars. It doesn't really hurt anything but your ears. You run rich for a millisecond and your car might burp a little backfire every once in a while but nothing detrimental to the engine.

Prove me otherwise?

I will agree that for our cars a recirculation type valve would be best. But I do not see a problem running an atmo-venting unit.
^ The man's right. I've been running a Greddy type S on my car for 20K + miles.
SUBARUEHS Racing
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Post by asc_up »

I've been running an HKS Super SQV for awhile now and I haven't had any problems. Occasionally I get a happy little backfire, but nothing crazy.
-Aaron

2000 Audi S4 - 2.7L Twin-turbo, 6 Speed

[quote="evolutionmovement"]It was me. And those are my balls. Happy Sunday![/quote]
94SS_Canada
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Post by 94SS_Canada »

YOu dont understand, there is no point to Blow it off when you can reuse it, its a waste of AIR pressure in my eyes, A blow-off valve is liking having a massive vacumm leak for a second into between shifts, Whats the fucking point?
FastRust
Imprezive
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Post by Imprezive »

I don't want to argue. He can go either way and be fine.
1992 T-Leg = 195whp 197wtq SOLD :(
1988 4Runner RIP
2006 Suzuki DRZ400sm
2007 Miata
1994 Miata
2003 WRX Wagon
2016 Mazda 3
asc_up
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Post by asc_up »

Yeah. There's no reason to get heated over this.

We're not saying that he shouldn't recirculate it, we're just saying that it's not going to harm his car or have a drastic effect on performance if he doesn't.
-Aaron

2000 Audi S4 - 2.7L Twin-turbo, 6 Speed

[quote="evolutionmovement"]It was me. And those are my balls. Happy Sunday![/quote]
i_c_the_light
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Post by i_c_the_light »

94SS_Canada wrote:YOu dont understand, there is no point to Blow it off when you can reuse it, its a waste of AIR pressure in my eyes, A blow-off valve is liking having a massive vacumm leak for a second into between shifts, Whats the fucking point?
A car that goes PPPPSSSSSSSHHHHHH, hot chicks and exhaust flames.
1990 Legacy GT wagon. 100% JDM, 100% factory.
Imprezive
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Post by Imprezive »

[quote="i_c_the_
A car that goes PPPPSSSSSSSHHHHHH, hot chicks and exhaust flames.[/quote]

Hmmm, I've yet to see any hot chicks attracted to my subi. Maybe I need some exhaust flames? Or maybe some graphics painted on my hood...
1992 T-Leg = 195whp 197wtq SOLD :(
1988 4Runner RIP
2006 Suzuki DRZ400sm
2007 Miata
1994 Miata
2003 WRX Wagon
2016 Mazda 3
94SS_Canada
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Post by 94SS_Canada »

Imprezive wrote:I don't want to argue. He can go either way and be fine.
Not arguing, just saying if you dont want to its not going to gain you any performance.
FastRust
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Post by Fkyx »

Imprezive wrote:Hmmm, I've yet to see any hot chicks attracted to my subi. Maybe I need some exhaust flames? Or maybe some graphics painted on my hood...
lol. I'm in the same boat... Although some of the guys from New Zealand who go to my school have been eyeing my ride for quite a while now.
Matthew aka F[b][color=red]k[/color][/b]yx
1991 Legacy Sport Sedan "Jillian" - [url=http://bbs.legacycentral.org/viewtopic.php?t=39548]EJ20G swap[/url]
asc_up
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Post by asc_up »

Hahaha yeah I seem to have the same problem. Although it is fun if there's an unsuspecting person walking on the side of the rode and you make your BOV go off right next to them. Ahaha.
-Aaron

2000 Audi S4 - 2.7L Twin-turbo, 6 Speed

[quote="evolutionmovement"]It was me. And those are my balls. Happy Sunday![/quote]
i_c_the_light
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Post by i_c_the_light »

Imprezive wrote: Hmmm, I've yet to see any hot chicks attracted to my subi. Maybe I need some exhaust flames? Or maybe some graphics painted on my hood...
I never thought of the graphics...I do have a Greenpeace sticker...but it's a bit ironic since the Legacy is a UHEV.
1990 Legacy GT wagon. 100% JDM, 100% factory.
Imprezive
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Post by Imprezive »

LOL. That would be great! Just tell everyone it runs off of propane and pixie dust.

gotta love the sleeper-ness of these cars tho. Had a guy in a '04 wrx race me yesterday. I won. Then we stopped at the next light red light and he wouldnt look at me. :P
1992 T-Leg = 195whp 197wtq SOLD :(
1988 4Runner RIP
2006 Suzuki DRZ400sm
2007 Miata
1994 Miata
2003 WRX Wagon
2016 Mazda 3
i_c_the_light
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Post by i_c_the_light »

Yeah that TD05 would've made things entertaining.

All I get is kids in VTEC puddle jumpers who claim to have wasted some guy in a dubbie.

I.D.C. = I Don't Care.
1990 Legacy GT wagon. 100% JDM, 100% factory.
RJ93SS
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Post by RJ93SS »

let's clear this up,

disconnect your bpv hose and plug the intake side off so your intake isnt sucking in unmeasured air, go for a drive up a hill and giver her, see how shitty your car runs.

use the new blow off but recirc it, youll still her it and your car will run proper
93SS 04 wrx brakes/slotted w/ hawks--TD05 -- 06 I/C -- 20mm n/a fsb -- Stage 2 -- 550's -- Perrin DIV DP -- 2-3/4 Tit Exhaust -- K&N -- C/C -- A/C Delete -- Grounded -- GT Leather Interior -- WRX/STI Strut Setup -- 17" 225's -- 2 Kids Seats ;)
asc_up
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Post by asc_up »

RJ93SS wrote:let's clear this up,

disconnect your bpv hose and plug the intake side off so your intake isnt sucking in unmeasured air, go for a drive up a hill and giver her, see how shitty your car runs.

use the new blow off but recirc it, youll still her it and your car will run proper

That will not imitate a BOV correctly. The stock BPV stays open during idle which is basically a giant vacuum leak if it is not recirculated. A BOV stays closed at idle so it doesn't create a vacuum leak.

For what it's worth, I've been running an HKS Super SQV BOV for a few months now and the car runs just as well as it did stock.
-Aaron

2000 Audi S4 - 2.7L Twin-turbo, 6 Speed

[quote="evolutionmovement"]It was me. And those are my balls. Happy Sunday![/quote]
New92
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Post by New92 »

RJ93SS wrote:let's clear this up,

disconnect your bpv hose and plug the intake side off so your intake isnt sucking in unmeasured air, go for a drive up a hill and giver her, see how shitty your car runs.

use the new blow off but recirc it, youll still her it and your car will run proper
I know that everyone has had different experiences with this. My own personal attempt was with a 1G DSM factory BOV at 12psi. The car ran like a bleeding gazelle in a lion refuge under full acceleration however if I kicked in the clutch to slow down or stop the engine would stumble and or die. I had to hold in the accelerator just to keep it going at stops untill I got home. So I piped it back to the stock recirc location and all is well. And yes, with the mods like MUG, K&N, and desnork you will hear it quite well when you let off the gas.
1992 SS 5MT
She's growing faster in her old age!
asc_up
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Post by asc_up »

New92 wrote:
RJ93SS wrote:let's clear this up,

disconnect your bpv hose and plug the intake side off so your intake isnt sucking in unmeasured air, go for a drive up a hill and giver her, see how shitty your car runs.

use the new blow off but recirc it, youll still her it and your car will run proper
I know that everyone has had different experiences with this. My own personal attempt was with a 1G DSM factory BOV at 12psi. The car ran like a bleeding gazelle in a lion refuge under full acceleration however if I kicked in the clutch to slow down or stop the engine would stumble and or die. I had to hold in the accelerator just to keep it going at stops untill I got home. So I piped it back to the stock recirc location and all is well. And yes, with the mods like MUG, K&N, and desnork you will hear it quite well when you let off the gas.
Which brings me back to the point I made. The reason it didn't idle when you put in the clutch is because the BPV opened up at idle which caused a huge vacuum leak, hence the shitty idle.
-Aaron

2000 Audi S4 - 2.7L Twin-turbo, 6 Speed

[quote="evolutionmovement"]It was me. And those are my balls. Happy Sunday![/quote]
Imprezive
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Post by Imprezive »

If you want atmo-venting, buy a true atmospheric blow off valve.

If you want recirculation then keep your original bypass valve or buy a true aftermarket recirculation valve and figure out a way to recirculate it.

Atmo-venting does NOT make your car run like shit unless your BOV has a vacuum leak, or changing your car to an atmo-venting style valve has caused some kind of vacuum leak.

Simply put, the air that the MAF has metered but is being released to the atmosphere would not be going into the engine anyway because it is recirculated to the intake and obviously if the BOV is open your throttle plate is closed or closing, creating a vacuum which opens your BOV. So that air isnt going to get in there anyway until you press the gas again.

Either way works. Case closed.
1992 T-Leg = 195whp 197wtq SOLD :(
1988 4Runner RIP
2006 Suzuki DRZ400sm
2007 Miata
1994 Miata
2003 WRX Wagon
2016 Mazda 3
RJ93SS
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Post by RJ93SS »

asc_up wrote:
RJ93SS wrote:let's clear this up,

disconnect your bpv hose and plug the intake side off so your intake isnt sucking in unmeasured air, go for a drive up a hill and giver her, see how shitty your car runs.

use the new blow off but recirc it, youll still her it and your car will run proper

That will not imitate a BOV correctly. The stock BPV stays open during idle which is basically a giant vacuum leak if it is not recirculated. A BOV stays closed at idle so it doesn't create a vacuum leak.

For what it's worth, I've been running an HKS Super SQV BOV for a few months now and the car runs just as well as it did stock.
my bad, i didn't know that
93SS 04 wrx brakes/slotted w/ hawks--TD05 -- 06 I/C -- 20mm n/a fsb -- Stage 2 -- 550's -- Perrin DIV DP -- 2-3/4 Tit Exhaust -- K&N -- C/C -- A/C Delete -- Grounded -- GT Leather Interior -- WRX/STI Strut Setup -- 17" 225's -- 2 Kids Seats ;)
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