Welcome to the North American Subaru Impreza Owners Club Wednesday April 16, 2014
Home Forums WikiNASIOC Products Store Modifications Upgrade Garage
NASIOC
Here you can view your subscribed threads, work with private messages and edit your profile and preferences Home Registration is free! Visit the NASIOC Store NASIOC Rules Search Find other members Frequently Asked Questions Calendar Archive NASIOC Upgrade Garage Logout
Go Back   NASIOC > NASIOC Technical > Normally Aspirated with bolt-on Forced Induction Powertrain

Welcome to NASIOC - The world's largest online community for Subaru enthusiasts!
Welcome to the NASIOC.com Subaru forum.

You are currently viewing our forum as a guest, which gives you limited access to view most discussions and access our other features. By joining our community, free of charge, you will have access to post topics, communicate privately with other members (PM), respond to polls, upload content and access many other special features. Registration is free, fast and simple, so please join our community today!

If you have any problems with the registration process or your account login, please contact us.
* Registered users of the site do not see these ads.
Reply
 
Thread Tools Display Modes
Old 05-30-2004, 01:26 PM   #1
masiolli
Scooby Newbie
 
Member#: 35840
Join Date: Apr 2003
Location: Youngstown, Oh
Vehicle:
1999 Blue RS-t
22t & Hydra

Default RS-t related question...

Sorry if these are n00b questions.. but they've been bothering me cause i dont know why its like this..

ok first off.... how come my car doesnt make boost in neutral? I know someone with a 02 WRX, and he can rev it, and let off the gas and his BOV goes off... but mine stops at 0PSI... i dont really care so dont flame me for wanting to hear my BOV work... i'm just confused on why mine is like that...

second: How come my BOV only goes off when the car is in neutral.. by this i mean... im in first, i floor it, make boost... let off the gas.. nothing.. i do the same thing, but this time, when i let off the gas, i put it in neutral... my BOV vents... why does is doing this? i thought the BOV vented the air when the throttle body closed... i have a feeling it has something to do with the vacuum system (which i completely dont understand..).

Thanks for the help... again... forgive my n00biness...
* Registered users of the site do not see these ads.
masiolli is offline   Reply With Quote
Old 05-30-2004, 01:31 PM   #2
White 2.5rs
Scooby Guru
 
Member#: 39936
Join Date: Jul 2003
Vehicle:
99RS TWE&SCAT EJ257
Hydra+HMist+PPG+35R=DEATH

Default

its in ur head man, im not joking

that not blowing w/ just revving might be a characteristic of ur turbo setup/piping

Last edited by White 2.5rs; 05-30-2004 at 01:45 PM.
White 2.5rs is offline   Reply With Quote
Old 05-30-2004, 01:34 PM   #3
masiolli
Scooby Newbie
 
Member#: 35840
Join Date: Apr 2003
Location: Youngstown, Oh
Vehicle:
1999 Blue RS-t
22t & Hydra

Default

so do all the RS-t's do this? or is mine wrong? cause i bought it with the turbo kit on (minnam stage 2) and the guy who put it on didnt do the best job....
masiolli is offline   Reply With Quote
Old 05-30-2004, 01:47 PM   #4
Unsung Boxer
Scooby Specialist
 
Member#: 37196
Join Date: May 2003
Location: WA state
Default

the Blow off valve works like this:

1. Spring pressure helps hold the valve shut.
2. Vacuum line sucks valve open under hard vacuum.
3. Boost pressure pushes valve open from other side.

Everyone forgets number 3.

What im getting at is that your BOV will only open when there is a significant "change in" pressure.

Its hard to get the BOV to blow in neutral. You usually have to goose the gas pedal. If spring pressure is too high, or you are using a poor vacuum source, it might not go. Its not really necessary for it to blow in neutral revving.

If its not blowing off in normal shifting, you are going to have to address the 3 things that make it work. Most likely the spring is set too tightly.

-Jake
Unsung Boxer is offline   Reply With Quote
Old 05-30-2004, 07:22 PM   #5
Avenger
Scooby Specialist
 
Member#: 1234
Join Date: Apr 2000
Location: Vancouver, Canada
Vehicle:
2000

Default

Quote:
ok first off.... how come my car doesnt make boost in neutral? I know someone with a 02 WRX, and he can rev it, and let off the gas and his BOV goes off... but mine stops at 0PSI... i dont really care so dont flame me for wanting to hear my BOV work... i'm just confused on why mine is like that...
Your turbo is a t3/t4, it is a fairly big turbo and takes more exhaust to get it spooling. Whereas the turbo on the wrx is smaller and it doesn't take as much exhaust to get the turbo to spool up and create boost.
Avenger is offline   Reply With Quote
Old 05-30-2004, 07:45 PM   #6
kaos200
Scooby Guru
 
Member#: 2692
Join Date: Oct 2000
Chapter/Region: SCIC
Location: SoCal
Default

Quote:
Originally posted by Avenger
Your turbo is a t3/t4, it is a fairly big turbo and takes more exhaust to get it spooling. Whereas the turbo on the wrx is smaller and it doesn't take as much exhaust to get the turbo to spool up and create boost.
in short
baby turbos blow off easy
big boy turbos dont
kaos200 is offline   Reply With Quote
Old 06-01-2004, 05:35 PM   #7
masiolli
Scooby Newbie
 
Member#: 35840
Join Date: Apr 2003
Location: Youngstown, Oh
Vehicle:
1999 Blue RS-t
22t & Hydra

Default

so do all the RS-t's do this?
masiolli is offline   Reply With Quote
Old 06-01-2004, 06:22 PM   #8
Hitokiri
Scooby Specialist
 
Member#: 2604
Join Date: Oct 2000
Chapter/Region: NESIC
Location: CA
Vehicle:
1999 2.5RSt
RBP

Default

Quote:
Originally posted by kaos200
in short
baby turbos blow off easy
big boy turbos dont
well, Like Kaos200 said. If you have a large enough turbo so that it does not produce enough pressure in neutral to cause the BOV to open, then you won't hear the valve open.

If you have a WRX turbo powering your RSt, chances are it will spool a little and provide enough pressure to open the BOV, thus producing the noise.

But there are many factors that go into whether the BOV opens including many aspects of the turbo setup. An "RSt" can be setup many different ways producing different results.

So to finally answer your question:
no RSt's don't all behave like you described. Some will blow off and some won't.
Hitokiri is offline   Reply With Quote
Old 06-01-2004, 06:25 PM   #9
masiolli
Scooby Newbie
 
Member#: 35840
Join Date: Apr 2003
Location: Youngstown, Oh
Vehicle:
1999 Blue RS-t
22t & Hydra

Default

alright... i just wanted to know if something wasnt hooked up right
masiolli is offline   Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
Visiting Montreal Tomorrow have some non GP related questions tifosi77 Canada Region Forum 3 06-05-2002 01:39 PM
2 quick un related questions Lifino General Forum Archive 6 11-08-2000 12:46 AM
Md or Va Impreza owners - I have an Impreza related question. Snoopy General Forum Archive 1 06-05-2000 08:08 AM
Spin-out Tire related question N/A General Forum Archive 6 06-04-2000 03:47 AM


All times are GMT -4. The time now is 12:59 AM.


Powered by vBulletin® Version 3.7.0
Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
Powered by Searchlight © 2014 Axivo Inc.
Copyright ©1999 - 2014, North American Subaru Impreza Owners Club, Inc.