Just Got A Wrx Today. Questions
Results 1 to 9 of 9

This is a discussion on Just Got A Wrx Today. Questions within the New Member Hangout forums, part of the Community - Meet other Enthusiasts category; Ok My wife came home with a 2004 WRX today that we decided to purchase. It has 10,000 miles on ...

  1. #1
    Registered User
    Join Date
    Sep 2005
    Posts
    8

    Just Got A Wrx Today. Questions

    Ok
    My wife came home with a 2004 WRX today that we decided to purchase. It has 10,000 miles on it. Anyway the car is slightly modified. I noticed it has an aftermarket mufler which sounds good. The SUBARU letters were removed from the trunk which is nice too. HOWEVER, it has a GReddy blow off valve installed. The old parts that were removed to put this on are in the trunk in a box. I hear theese BOVs are bad for the car. It makes a loud hiss when you shift gears. My question is, do i remove the BOV?

    We both love the car. Its BRIGHT blue with a 5 speed and a sunroof. It also has the "cold weather package?" which means it has heated seats.

    Anyone got any idea what I should do to the car? It will be a daily driver and all around fun car.

    Thanks

    Chris

  2. Remove Advertisements
    ClubWRX.net
    Advertisements
     

  3. #2
    Registered User erockWRX's Avatar
    Join Date
    May 2005
    Location
    NW Chicago Subs
    Posts
    68
    first off, welcome. You will love this car. As for the bov, I would say remove it and put the stock one back on. I was in the same situation as you when I got my wrx and it runs much smoother with the stock bov. Some people will arguee and say that there is nothing wrong with running an aftermarket bov, and they might be right. All I can tell you is that many of us had idle problems and my car used to "lurch" when shifting under very high load. While the sound is nice and all, I would take it off and have some fun in your new car. Good luck and keep us posted.

  4. #3
    Registered User
    Join Date
    Aug 2005
    Location
    Longmont, CO
    Posts
    69
    the "hiss" sound is what people go for with BOV's the stock one does too, just quieter. You would be fine with an aftermarket BOV if you had a cat-less up pipe. and had it recirculated. If not, it wears down the cat in the up-pipe and sends metal into the turbo, and that = no good. I think it might do something to your cat in your downpipe as well, but I am not sure.
    Latest surveys show that 3 out of 4 people make up 75% of the world's population...

  5. #4
    Registered User WRXcelration's Avatar
    Join Date
    Apr 2004
    Location
    Allentown PA
    Posts
    2,797
    welcome to the club....if its the type s then it it should b recirculating.....you could adjust it or just put it back to stock..up to you
    05 STI

    Speed Comes At A Price...How Fast Can You Afford To Go?

  6. #5
    Registered User sparky814's Avatar
    Join Date
    Sep 2005
    Location
    Chico, CA
    Posts
    4
    Congrats on the purchase.... I am sure by now you have figured out that this car is one of the best (or at least the most fun) sports cars out there! I have added an HKS super sequential BOV to my WRX and noticed nothing wrong with the performance. As I have been told, the stock bypass valve recirculates the air back into the intake system which when shifting causes back pressure. First off, I heard that slows the turbo as it is free wheeling which wears on the turbo. The after market BOV has the whooshing noise that is let off into the atmosphere, letting the turbo freewheel, in theory reducing lag and stress. So as I know it, there is no danger of having it on the car.
    The power lag that was mentioned in one of the threads is something I had too, but I remedied it by installing an AEM cold air intake and now the lag is gone. This ofcourse was found through dumb luck, but hey I'll take it where I can get it!!

  7. #6
    Moderator
    Join Date
    Jul 2003
    Location
    Maryland
    Posts
    11,098
    I Support ClubWRX
    Holy misinformation batman....for starters the two worst mods for a stock wrx are BOV and CAI.

    The bov's have been known to cause a rich condition during shifts which isnt good for that split second the car is in transition. For your 04 it most likely suffers from a CL/OL issue that many of them suffer from. It takes awhile for the fuel map to catch up once you mash the gas, so your rpms are high without the right fuel. I'd put the stock BOV back on, and if you want to reduce turbo lag look at Uppipes and downpipes. Good luck.
    0-60 faster then your first sexual experience.
    "You've come far, and though you're far from the end
    You don't mind where you are, cause you know where you've been"

  8. #7
    Registered User
    Join Date
    Sep 2005
    Location
    Charlotte, NC
    Posts
    59
    the WRX comes with a bypass valve, not a BOV. The bypass valve actually recirculates the exhaust through the intake actually letting the turbo remain spinning after you've let off the gas which means faster spool time once you hit the gas again which means more boost earlier on to get your car going. An aftermarket BOV isn't necessary until you're pushing over 20psi from the turbo when a BOV is necessary to release that excess preassure. If the aftermarket recirculates too it's fine(some do) but I'd assume it doesn't and you should put the stock bypass valve back on until you've done mods yourself, mainly an aftermarket or gutted up pipe so your CAT doesn't get destroyed and thrown into your turbo destroying that which will be expensive to fix.

  9. #8
    Moderator YBNormal07's Avatar
    Join Date
    Jul 2003
    Location
    PA
    Posts
    6,238
    I Support ClubWRX
    Hi, and welcome to the club.

    Review the sticky on "good first mods" as this will likely give you idea's for what you can do within you goals and budget.

    A BOV will not actually hurt your car, but it does cause intermittant issues with the inlet air flow measurement, which confuses the ECU a bit, resulting a spurious rich conditions, which can cause a rough idle and stumbling between shifts. If the one on you car is adjustable in regards to recirculation, and you find the hiss annoying, just set it for 100% recirc and be done.

    A cold air intake tends to mask the effects of a BOV by leaning the engine out. Without EM though, this isn't be most ideal situation as the lean condition can be problematic during throttle lift off periods, possibly promoting abnormal engine wear over a long duration.

    If you have an aftermarket exhaust, you may want to double check to see if you also have an aftermarket down pipe and/or up pipe, as it is rare to find a WRX with just a different muffler.

    My recommendation is that if you want just a bit more performance value out of it, but don't need any hastle's about emissions, just put an up pipe on it. It makes the throttle response much faster, and feels like a different car.

    From there, a down pipe and EM might be in the cards. Gotta run....staff meeting!
    tEh PriUs=teH faSTah!@@!
    SOLD: 05 SWP Legacy GT Limited 5MT, 13.3ish@105 (stage 2) crappy stock clutch
    SOLD: 04 MPS/SW WRX Sti. 12.971 @ 103.97 (stock)
    278 AWHP/283 AWT, Catback exhaust
    306 AWHP/341 AWT, Stage 2
    (Scott) Moderator-STi, Drag Racing, Car Purchasing, and Tutorial Forums

  10. #9
    Registered User
    Join Date
    Apr 2004
    Location
    Charleston, WV
    Posts
    1,617
    Welcome, glad that you joined up! Have fun with a very fun car!!
    04 PSM WRX Stg 4-16G
    Blobeye Syndicate

Posting Permissions

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