Welcome to the North American Subaru Impreza Owners Club Saturday October 20, 2018
Home Forums WikiNASIOC Products Store Modifications Upgrade Garage
NASIOC
Go Back   NASIOC > NASIOC Technical > Factory 2.0L Turbo Powertrain (EJ Series Factory 2.0L Turbo)

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 07-16-2018, 04:59 PM   #1
Max2003WRX
Scooby Newbie
 
Member#: 487816
Join Date: Jun 2018
Location: Cincinnati, Ohio
Vehicle:
2003 Impreza WRX
WR Blue

Default Bigger/ better boost

So I'm still pretty new to cars, but I've learned a lot over the past couple months. I have an 03 wrx and I was wondering if there was a way to use my COBB accessport to make my turbo spool sooner and/or increase the maximum PSI. Right now, I max out at around 11 PSI when in 4th gear at 6000 rpm. Any speed below 60 MPH and I get around 9 PSI boost at best. What can I do to get more boost??? (I already have an SPT intake and exhaust, nvidia up and down pipes)

PS - I might look into a new turbo. How much are they and what would you recommend?
* Registered users of the site do not see these ads.
Max2003WRX is offline   Reply With Quote
Sponsored Links
* Registered users of the site do not see these ads.
Old 07-16-2018, 07:23 PM   #2
CarmelValleyWRX
Scooby Specialist
 
Member#: 453872
Join Date: Sep 2016
Vehicle:
2005 wrx wagon
48w

Default

you need to tune your car so it stops knocking and then you can get the stock 14.5psi of boost at least. then worry about turning up the boost once its running half way descent. a "stage 2" map would probably get it running pretty well.
CarmelValleyWRX is offline   Reply With Quote
Old 07-16-2018, 07:55 PM   #3
Max2003WRX
Scooby Newbie
 
Member#: 487816
Join Date: Jun 2018
Location: Cincinnati, Ohio
Vehicle:
2003 Impreza WRX
WR Blue

Default

Quote:
Originally Posted by CarmelValleyWRX View Post
you need to tune your car so it stops knocking and then you can get the stock 14.5psi of boost at least. then worry about turning up the boost once its running half way descent. a "stage 2" map would probably get it running pretty well.
So do I just make a map of my current setup and send it to COBB and ask for a stage 2 map? what are the drawbacks of this?
Max2003WRX is offline   Reply With Quote
Old 07-16-2018, 08:16 PM   #4
CarmelValleyWRX
Scooby Specialist
 
Member#: 453872
Join Date: Sep 2016
Vehicle:
2005 wrx wagon
48w

Default

well with the mods you have the engine is over boosting, which means the turbo is spinning faster than expected. the intake you have is making it run lean. both of these things cause "knock" which is when the air and fuel kind of explode uncontrollably which is not good. the car detects it and tries to save it self by limiting your boost and reducing ignition timing. that is why you only have 8-10psi right now. a stage 2 map is already done and you just load it onto the cars ecu. it will adjust the ignition timing and bring the turbo back under control. you should take the intake off and put the stock air box back on. it works great. you can use an accessport or a tactrix to flash a stage 2 or a custom map.
CarmelValleyWRX is offline   Reply With Quote
Old 07-16-2018, 08:37 PM   #5
Brother EddieJ.
Scooby Specialist
 
Member#: 181617
Join Date: Jun 2008
Chapter/Region: MAIC
Location: frederick, md
Vehicle:
2004 wrx
6speed/ 330whp/ 300wtq

Default

https://forums.nasioc.com/forums/sho...d.php?t=533787

Read this ^^^^^^^ all of it. Stay to the noob section. Read their stickies, all of them. Read way way more, post way way less. Any question you have has been asked and answered. Trust me everything you could ever want to know is here, just search.
Brother EddieJ. is offline   Reply With Quote
Old 07-17-2018, 07:27 AM   #6
Max2003WRX
Scooby Newbie
 
Member#: 487816
Join Date: Jun 2018
Location: Cincinnati, Ohio
Vehicle:
2003 Impreza WRX
WR Blue

Default

Quote:
Originally Posted by Brother EddieJ. View Post
https://forums.nasioc.com/forums/sho...d.php?t=533787

Read this ^^^^^^^ all of it. Stay to the noob section. Read their stickies, all of them. Read way way more, post way way less. Any question you have has been asked and answered. Trust me everything you could ever want to know is here, just search.
Thank you
Max2003WRX is offline   Reply With Quote
Old 07-23-2018, 01:21 AM   #7
BugeyeJay
Scooby Newbie
 
Member#: 445146
Join Date: Apr 2016
Chapter/Region: Tri-State
Location: New Jersey
Vehicle:
2002 WRX
Silver

Default

I think you should check for vacuum leaks. In my experience when you overboost, you get boost oscillation but when you have a vacuum leak you get slow spool and under boost. Your car is fine with the SPT intake. They were sold with stock cars and if Iím not mistaken keeps the stock MAF diameter. The stage 2 tune should really wake the car up
BugeyeJay is offline   Reply With Quote
Old 07-26-2018, 12:08 AM   #8
Max2003WRX
Scooby Newbie
 
Member#: 487816
Join Date: Jun 2018
Location: Cincinnati, Ohio
Vehicle:
2003 Impreza WRX
WR Blue

Default

Quote:
Originally Posted by BugeyeJay View Post
I think you should check for vacuum leaks. In my experience when you overboost, you get boost oscillation but when you have a vacuum leak you get slow spool and under boost. Your car is fine with the SPT intake. They were sold with stock cars and if Iím not mistaken keeps the stock MAF diameter. The stage 2 tune should really wake the car up
checked for vacuum leak when replacing my valve cover gaskets, sure enough there was a leak. Hitting target boosts now, thanks!
Max2003WRX is offline   Reply With Quote
Old 07-27-2018, 12:16 PM   #9
contaminatrix
Scooby Newbie
 
Member#: 435611
Join Date: Dec 2015
Chapter/Region: International
Location: Nairobi
Vehicle:
2002 SG5-2.0-XT-JDM
45A, originally 18L

Default

Quote:
Originally Posted by Max2003WRX View Post
checked for vacuum leak when replacing my valve cover gaskets, sure enough there was a leak. Hitting target boosts now, thanks!
where was the leak exactly if you may? it may help someone in future. thanks.
contaminatrix 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

All times are GMT -4. The time now is 09:42 PM.


Powered by vBulletin® Version 3.7.0
Copyright ©2000 - 2018, Jelsoft Enterprises Ltd.
Powered by Searchlight © 2018 Axivo Inc.
Copyright ©1999 - 2017, North American Subaru Impreza Owners Club, Inc.