"The BIG BOV thread" (Where all bov question threads get merged) - Page 731

This is a discussion on "The BIG BOV thread" (Where all bov question threads get merged) within the Engine Modifications forums, part of the Tech & Modifying & General Repairs category; Originally Posted by bkallday27 if you get a blow off valve get a dual vented one. it still gives you ...

  1. #10951
    Moderator Donkey's Avatar
    Join Date
    Apr 2005
    Location
    Da boonies
    Posts
    6,051
    I Support ClubWRX
    Quote Originally Posted by bkallday27 View Post
    if you get a blow off valve get a dual vented one. it still gives you that signature sound but also keeps some boost into the engine
    Pretty sure hybrid "50/50" BOV has been mentioned a couple of times in the first 10,000 posts in this thread....
    Resident Adviser @ WTF Tuning, LLC
    2002 FORESTER S
    1998 FORESTER S




  2. Remove Advertisements
    ClubWRX.net
    Advertisements
     

  3. #10952
    Pro Manscaper Mikie13's Avatar
    Join Date
    Oct 2006
    Location
    Palmyra, NJ
    Posts
    20,768
    Bump since we haven't touched this thread in over a month



    PSSSSSSSSSSSSSSSSSHHHHHHHHHHHHHHHHH!!!!!!!!!!!!
    The Hawk-Eye Alliance #90|The Blobeye Syndicate #0|The Stink-Eye Mob #0|N.E.R.D. Founding Member & #3
    2012 Lightning Red WRX Sedan Stock...for now Soon to be OpenSource tuned by: Mattypants @ WTF Tuning
    "If I have 10 ice cubes and you have 11 giraffes, how many pancakes can fit on the roof? Purple, because aliens donít wear hats" -Ying

  4. #10953
    Registered User 2005sti's Avatar
    Join Date
    Jan 2010
    Location
    Trinity, NC
    Posts
    188
    Ive read about the BOV causing a wrx to run rich between shifts. I have an 05 WRX and want a BOV. I can get my car tuned to run perfectly fine with a BOV, correct?
    2005 Subaru Impreza WRX - FP 68HTA'd
    2007 Honda Civic Si (Stock) - Traded it for ^^^

    Blobeye Syndicate #728

  5. #10954
    Geriatric Ginger Mod Rogan's Avatar
    Join Date
    May 2007
    Location
    behind the wheel
    Posts
    8,188
    I Support ClubWRX
    you can't really tune for air that is lost.
    Rogan o_0
    '96 Dodge 2500 CTD @ 40psi - over 700 lb/ft TQ, 7" stack, and 5speed! - SOLD
    '01 Dodge 2500 CTD 6-holed hand-shaker - 3850# dual disk - 900 lb/ft - SOLD
    '97 Dodge 3500 CTD DUALLY built Auto - 40psi boosties - 750 lb/ft

  6. #10955
    Registered User 2005sti's Avatar
    Join Date
    Jan 2010
    Location
    Trinity, NC
    Posts
    188
    so really, there is no way to vent my BOV to the atmosphere (in any shape, form or fashion) or get an aftermarket BOV, get it tuned, and have it run perfectly fine?
    2005 Subaru Impreza WRX - FP 68HTA'd
    2007 Honda Civic Si (Stock) - Traded it for ^^^

    Blobeye Syndicate #728

  7. #10956
    Geriatric Ginger Mod Rogan's Avatar
    Join Date
    May 2007
    Location
    behind the wheel
    Posts
    8,188
    I Support ClubWRX
    not unless you reconfigure it for blow-thru and run a non-stock EMS, and place the BOV pre-metered air, No.


    Or go Speed Density.
    Rogan o_0
    '96 Dodge 2500 CTD @ 40psi - over 700 lb/ft TQ, 7" stack, and 5speed! - SOLD
    '01 Dodge 2500 CTD 6-holed hand-shaker - 3850# dual disk - 900 lb/ft - SOLD
    '97 Dodge 3500 CTD DUALLY built Auto - 40psi boosties - 750 lb/ft

  8. #10957
    Registered User 2005sti's Avatar
    Join Date
    Jan 2010
    Location
    Trinity, NC
    Posts
    188
    can you dumb that up for me a little? Im not all that great with cars and their fancy young, hip lingo. Please dont hate me, just trying to understand.
    Last edited by 2005sti; 02-10-2010 at 07:28 PM.
    2005 Subaru Impreza WRX - FP 68HTA'd
    2007 Honda Civic Si (Stock) - Traded it for ^^^

    Blobeye Syndicate #728

  9. #10958
    Geriatric Ginger Mod Rogan's Avatar
    Join Date
    May 2007
    Location
    behind the wheel
    Posts
    8,188
    I Support ClubWRX
    Quote Originally Posted by 2005sti View Post
    can you dumb that up for me a little? Im not all that great with cars and their fancy young, hip lingo. Please dont hate me, just trying to understand.
    well, at over 40, you won't get the young hip lingo from me.

    In a nutshell:
    air enters through the filter, then into the intake tube/Mass Airflow Sensor. This reads the airflow rate, and then tells the ecu how much is coming in. Then the ecu fuels according to that 'metered' air that has passed through the MAS sensor, so the air/fuel mixture is correct. When a BOV dumps that 'metered' or 'measured' air, then the fuel that has been programmed to deliver now is more than is needed, throwing the air/fuel ration way to the RICH side. This can/does/will cause cylinder wash (where the gasoline removed the oil coating on the cylinder walls, because there isn't enough air to fully atomize the mixture. This also will cause a rapid change in piston/combustion chamber temperature, then back to hot again, and a super fast rate. At 5000+rpm, you can only imagine what this can do over a fairly short period of time. Some engine react more to this change than others. Some don't make apparent reactions to this, but the issue is still there, and happens across the board.
    The oxygen sensor reads this real rich situation, and tells the ecu to take fuel out, about the time you're back into the throttle. You just had a rich condition, now it goes lean, then back to rich, and so on.

    With a speed density setup (say, like a honda, with a MAP sensor), it reads the manifold pressure and makes fueling determinations from that. So a BOV opening up, drops the manifold pressure, and the ecu takes fuel out, making this no longer an issue.
    Same above goes for a blow-through setup, where the MAS semsor is downstream of the BOV, so the vented air hasn't been metered yet.

    A Subaru ECU and engine management system is very sophisticated and is quite sensitive to changes not programmed into it.

    If you're dead-set on the wooosh, cold-air intakes + stock BPVs will give you some sound. Not BOV style, but it will.
    At the outmost, 50/50 BOVs will not cause as much of a rich condition, but it still does. the stock BPV will handle up to 20psi easily, so it becomes a question of do you want performance, or 'hey, check me out! I drive a turbo cah!'


    How's that?


    For you, if you go turbo-back exhaust, CAI, and Stg2 Cobb or RomRaider OpenSource flash, you'll be surprised how much quicker/faster/stronger your WRX will be. 200-220awhp is an eye-opener over stock. Your old honda wouldn't be able to hold it's nutsak. LOL

    Cheers
    Last edited by Rogan; 02-10-2010 at 08:13 PM.
    Rogan o_0
    '96 Dodge 2500 CTD @ 40psi - over 700 lb/ft TQ, 7" stack, and 5speed! - SOLD
    '01 Dodge 2500 CTD 6-holed hand-shaker - 3850# dual disk - 900 lb/ft - SOLD
    '97 Dodge 3500 CTD DUALLY built Auto - 40psi boosties - 750 lb/ft

  10. #10959
    UnBanned Sinister's Avatar
    Join Date
    Nov 2006
    Location
    Denver Metro Area
    Posts
    17,628
    I Support ClubWRX
    Well put Rogan.
    Kevin
    Moderator
    Sinister's Blowoff Valve FAQ
    WRX Gas Mileage FAQ
    Sinister's Progress Thread - 430whp 429wtq - Sold
    Firearms Enthusiasts Thread

    The Sheriff's Star at the bottom left corner rates a user's reputation.
    If you found a user's post to be helpful or quite the opposite, please make it known to them by clicking the Star!

  11. #10960
    Registered User 2005sti's Avatar
    Join Date
    Jan 2010
    Location
    Trinity, NC
    Posts
    188
    okay thanks! Ill just stick with the stock one and put a nice CAI on. :P

    thank you!
    2005 Subaru Impreza WRX - FP 68HTA'd
    2007 Honda Civic Si (Stock) - Traded it for ^^^

    Blobeye Syndicate #728

  12. #10961
    UnBanned Sinister's Avatar
    Join Date
    Nov 2006
    Location
    Denver Metro Area
    Posts
    17,628
    I Support ClubWRX
    Quote Originally Posted by 2005sti View Post
    okay thanks! Ill just stick with the stock one and put a nice CAI on. :P

    thank you!
    K&N Short ram, APS CAI, SPT short ram...

    That's what you're looking at.
    Kevin
    Moderator
    Sinister's Blowoff Valve FAQ
    WRX Gas Mileage FAQ
    Sinister's Progress Thread - 430whp 429wtq - Sold
    Firearms Enthusiasts Thread

    The Sheriff's Star at the bottom left corner rates a user's reputation.
    If you found a user's post to be helpful or quite the opposite, please make it known to them by clicking the Star!

  13. #10962
    Registered User
    Join Date
    Feb 2010
    Posts
    4

    BOV on stock engine

    i got a 2.0l turbo 2004 wrx, and I wanted to get a HKS blow off on it, i know it bad for stock engine and stock turbo, but I was wondering if I could still do it, without messing up too much.
    Last edited by Arnelis; 02-13-2010 at 03:26 PM.

  14. #10963
    Registered User sccoby823's Avatar
    Join Date
    Dec 2009
    Location
    New Bedford, Ma
    Posts
    341
    it causes the engine to run rich, because it messes with the MAF
    ***Stink Eye Mob 169***
    Stage 2 WRX Tuned by Brendan at Brentuning
    296 awhp
    317 awtq

  15. #10964
    Registered User 2w0r0x9's Avatar
    Join Date
    May 2009
    Location
    LBI, NJ
    Posts
    431
    Quote Originally Posted by Arnelis View Post
    i got a 2.0l turbo 2004 wrx, and I wanted to get a HKS blow off on it, i know it bad for stock engine and stock turbo, but I was wondering if I could still do it, without messing up too much.
    Dont waste the money..use the search function and search "intake silencer delete" this will get you the ricer pshhh sound you want

  16. #10965
    Moderator Donkey's Avatar
    Join Date
    Apr 2005
    Location
    Da boonies
    Posts
    6,051
    I Support ClubWRX
    Last edited by Donkey; 02-14-2010 at 07:38 AM.
    Resident Adviser @ WTF Tuning, LLC
    2002 FORESTER S
    1998 FORESTER S




Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •