How much performance can the OEM Bypass Valve handle?

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

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Subtle
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How much performance can the OEM Bypass Valve handle?

Post by Subtle »

This winter I intend to drop a TD05-16 turbo into my twgn.

It has a fmic, stainless exhaust(3-inch), stand alone SDS ecu, and a built 4eat. :)

Should I upgrade the bypass valve :?
Last edited by Subtle on Thu Dec 08, 2005 7:51 pm, edited 1 time in total.
Subtle (normally aspirated engines suck):
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62 Alfa Romeo Spider- had a 1.6 L with 80 hp, now 2 L with 160 torque. Curb weight 2050 lbs.
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Post by dzx »

TDO5H-16G? If you have a front mount, you might as well go to a bov. Greddy's bov can be recirculated.
///M
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Subtle
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Post by Subtle »

The current install is tidy and I prefer the recycle over the vent to the atmosphere type of valve.
Subtle (normally aspirated engines suck):
05 Legacy GT Wagon with Cobb chip.
62 Alfa Romeo Spider- had a 1.6 L with 80 hp, now 2 L with 160 torque. Curb weight 2050 lbs.
93 Leg Twgn fmic, vf34, etc. ((sold))
Subtle
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Post by Subtle »

What makes up the class 4 mods?
Subtle (normally aspirated engines suck):
05 Legacy GT Wagon with Cobb chip.
62 Alfa Romeo Spider- had a 1.6 L with 80 hp, now 2 L with 160 torque. Curb weight 2050 lbs.
93 Leg Twgn fmic, vf34, etc. ((sold))
555BCTurbo
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Post by 555BCTurbo »

I was running 19psi with a stock BPV, and it worked fine...
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Post by vrg3 »

I found it easier to fit a cheaply available Bosch BPV with my 16G than to try to make the OEM valve fit.
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wiscon_mark
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Post by wiscon_mark »

A member on SL-i modified a WRX Bypass Valve so it could take 24psi, I believe.

His username is Xcntrk75
[url=http://www.sl-i.net/FORUM/viewtopic.php?t=486]1995 Legacy Outback 5MT[/url]
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BAC5.2
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Post by BAC5.2 »

He just crushed it. Lots of people do that.

My stock valve was incapable of handling the air.

I've had various atmospheric BOV's and I can't wait to go back to recirculating.

Most good valves can be recirculated.
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Post by wiscon_mark »

I thought he beefed up the spring...
[url=http://www.sl-i.net/FORUM/viewtopic.php?t=486]1995 Legacy Outback 5MT[/url]
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Post by georryan »

555BCTurbo wrote:I was running 19psi with a stock BPV, and it worked fine...
Are you running any other engine management (ecu/piggyback/injectors)?
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Subtle
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Post by Subtle »

Geo

Stand alone SDS ecu, with down loadable wide-band, or whatever it' called.

Profec B controlling the waste gate. Set at 7.5 and 12.
Subtle (normally aspirated engines suck):
05 Legacy GT Wagon with Cobb chip.
62 Alfa Romeo Spider- had a 1.6 L with 80 hp, now 2 L with 160 torque. Curb weight 2050 lbs.
93 Leg Twgn fmic, vf34, etc. ((sold))
azn2nr
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Post by azn2nr »

my stock bpv on a fmic and 16g couldnt vent the air qick enough. lots of surge. holding was not a problem
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Subtle
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Post by Subtle »

BAC5.2

What ecu are you using :?

Thanks------- Bob
Subtle (normally aspirated engines suck):
05 Legacy GT Wagon with Cobb chip.
62 Alfa Romeo Spider- had a 1.6 L with 80 hp, now 2 L with 160 torque. Curb weight 2050 lbs.
93 Leg Twgn fmic, vf34, etc. ((sold))
White Out
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Post by White Out »

I am not sure if they use the same recirc valve, but my crushed oem held on the STi to 24psi.

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Post by 93Leg-c »

What does the term "crushed" mean?
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dzx
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Post by dzx »

Subtle wrote:What makes up the class 4 mods?
Aftermarket turbo kit
Engine management
FMIC
Cams
Fuel system
flywheel and stuff
?

I dunno, but i figure it would qualify for a stage 4 if there was one. :smile:
///M
'93 Legacy SS - part out
Legacy777
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Post by Legacy777 »

I hate the whole stage terminology....it's such bullshit. It means absolutely nothing. I have stage X from this company....well I have a stage X from another company.....Are all these companies going to get together and say, ok stage 1 has these parts, stage 2 has these parts, etc. Same goes for power increases.....

Anyway...my little rant.
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Post by dzx »

stage x, i like it. lol
///M
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Post by bmxpunk »

hahaha

dzx you have a stage 10 leggy!?!?!?!?!?


HAHAHAHA just kidding. roman numerals rule!!

agreed on not liking the stages though.
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Post by Legacy777 »

I was meaning X as in a variable ;)
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Post by bmxpunk »

I know. i guess i put the just kidding in the wrong spot.

as far a bpv input----my fried is using the leggy one on his rs-t works great 7psi ;)
2011 Mini Countryman S All4
1970 Honda Ct90
2001 Forester S of Doom - mowed down by a Cummins
1994/5/6/01/02/03/04/06/07/08 Impregacy OUtback SS STi Type R money pit- NEW RALLYCAR!!
Subtle
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Post by Subtle »

OK--the suspense is killing me.

What's a "crushed" bpv :?
Subtle (normally aspirated engines suck):
05 Legacy GT Wagon with Cobb chip.
62 Alfa Romeo Spider- had a 1.6 L with 80 hp, now 2 L with 160 torque. Curb weight 2050 lbs.
93 Leg Twgn fmic, vf34, etc. ((sold))
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Post by bmxpunk »

you crush the top of it inorder to add preload to the spring, making it feel stiffer
2011 Mini Countryman S All4
1970 Honda Ct90
2001 Forester S of Doom - mowed down by a Cummins
1994/5/6/01/02/03/04/06/07/08 Impregacy OUtback SS STi Type R money pit- NEW RALLYCAR!!
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Post by BAC5.2 »

Yep. Can't do it with a stock BPV though.

I wasn't running any engine management to speak of really.

I'll be doing things the right way soon enough though.
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2009 Impreza 2.5i Premium. Blue.

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Post by supermoose »

crush bov?

trick from the DSM guys. put bov in vise, ups the spring rate. duno personally, never done it.
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