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Blow off Valves on turbo motors

Posted: Tue Jan 03, 2006 7:34 pm
by wrx_nut
Are they any good>? ( prevent damage to turbo)
which ones do any of you guys use?
Sounds?
Plumback/atmospheric>?

whats the go when fitting one to an Ea82T stock manifold?


wrx_nut

Posted: Tue Jan 03, 2006 9:42 pm
by fredsub
plumb back..those atmospheric trumpets are for wankers :lol: :lol:
don't need anything fancy really, a Goyan industrial air valve is perfect for it
[img=http://img450.imageshack.us/img450/6184 ... 7mq.th.jpg]

Posted: Wed Jan 04, 2006 4:45 am
by MUDRAT
You should be able to pick up something adequate from Ebay for less than $50.

You should use a plumback with the EA82 turbo to avoid overfuel spikes when the valve opens.

The BOV is placed after the compressor and before the throttle body. Most come with a weld-in fitting, then use the grub screws suplied to fit the BOV to the fitting. The vac tube from the top needs a vacuum supply and the plumback must go back into the inlet on the vacuum side of the compressor and after your air flow meter.

Posted: Wed Jan 04, 2006 8:12 am
by Outback bloke
You need to know that plumb backs to do not work any better, they are just quiet. I have had both on my cars and prefer the queitness of the plumb back.

The car I have now has an atmo venting BOV only because there is no where to mount a plumb back. The noise shits me at times but it works just fine.

Posted: Wed Jan 04, 2006 8:36 am
by xaymaca
If you want a plumb-back BOV, I have one that came off my RX7. You can have it for nix if you go the plumb-back option.

It's not bright and blingy, it's just a black Denso unit that will look factory in your engine bay 8)

Posted: Wed Jan 04, 2006 10:48 am
by BlackMale
xaymaca, If he does not take it off ya hands i would be intersted as i am going to TMIC and scopp this would finish my coversion and the tri-fector. I will pay postage as well.

About not wanting cut any1's grass though.

Posted: Wed Jan 04, 2006 11:16 am
by MUDRAT
Yeah, there is the old annoyance factor. My old WRX would sit right on the threshold when cruising at 105-110km/h, so it would just be giving soft little "tshhhh . . . . tshhh . . . . tshhhh" constantly. Not fluttering, just barely on boost/then off.

Posted: Wed Jan 04, 2006 8:13 pm
by wrx_nut
what about those adjustable ones that change from atmos to plumback...
rip off or not?

GFB make them i think

Posted: Wed Jan 04, 2006 9:42 pm
by xaymaca
I guess you have a choice then... Personally on my RX7 I found a BOV was ridiculously annoying. I don't run a BOV, plumback or atmo - but that's another topic altogether.

You'll find that it's illegal to run an atmo BOV, so it would also be illegal to run an atmo/plumback as it has the option to be atmo.

All a case of whether you like a "Pschh" or a small and subtle "Whoosh" I guess.

Posted: Thu Jan 05, 2006 7:19 pm
by wrx_nut
anyone have any pictures or video's of blow off valves in operation>?
preferably on an ea82t

?

wrx_nut

Posted: Fri Jan 06, 2006 5:57 pm
by steve_rising_sun
I will send you a WRX unit with you engine, however on a small turbo the performance gain is not there. BOVs do not protect the turbo there lot in life is to reduce the slowing of the impeller at closed throttle.
Steve

Posted: Fri Jan 06, 2006 8:17 pm
by wrx_nut
that will be great steve
you have a PM

Posted: Sat Jan 07, 2006 12:47 am
by xaymaca
From looking at some pics, I believe my RX7 Denso unit is very similar (at least in shape) to the Subaru units.

Does anyone have a factory BOV hanging around they can take a photo of, and maybe write down the numbers on the side?

Posted: Sat Jan 07, 2006 4:20 pm
by Suby Wan Kenobi
I have an Atmo on my RX and the noise is annoying and i get some good back fires from the raw fuel dump in the pipe when changing gears somtimes. I will get around to a plumb back when i swap to the spidey manifold

Posted: Tue Jan 10, 2006 8:23 pm
by wrx_nut
any pics of all this?

Posted: Fri Jan 20, 2006 1:06 am
by spencer
this is a link to the gfb site with the adjustable bov
http://www.gfb.com.au/index.php?parenti ... stealth_fx

and a rather interesting devolped one
http://www.gfb.com.au/index.php?parenti ... ceptor_pro

i dont know alot about this stuff (only young and still learning :D ) but what about the hybrid bov's, not adjustable, but from my understanding, cause that vent to the atmosphere But also back in, this elimanates the fuel spike cause somethin to do with the airflow meter and so on. but the adjustable ones could b set up like a hybrid if u want cause u can choose how open the atmo vent is or vice versa with the plumback vent. but as i said before i dont know that much so what i have just said could be completly false. but the gfb site has a fair bit of info and they use a good car for the demo vids :lol:

Posted: Mon Jan 30, 2006 4:46 pm
by Phizinza
Best option for no ridiculuos sound and good preformance is have a plumback BOV and make sure it is hooked up to plumback between the air flow meter and the turbo, NOT into the airbox (un metered air.) You shouldn't have any problems with over fuel or what ever then. If you want sound and stupid feul consumption while comming off the turbo, just get a annoying "wankers" BOV.

Posted: Mon Jan 30, 2006 7:56 pm
by wrx_nut
yer i was thinking plumback....

i heard someone say the plumbacks still make a sound but not as rice as the atmosphere ones.. is that correct?

Posted: Mon Jan 30, 2006 8:11 pm
by Suba
Personally I think they sound quite good , and I am not saying this bacause I have one on the RS because I don't .

Mike.

Posted: Mon Jan 30, 2006 8:15 pm
by wrx_nut
some sound alright but there are the poofy ones