Welcome to the North American Subaru Impreza Owners Club Monday May 2, 2016
Home Forums WikiNASIOC Products Store Modifications Upgrade Garage
NASIOC
Go Back   NASIOC > NASIOC Technical > Factory 2.5L Turbo Powertrain (EJ Series Factory 2.5L 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 09-15-2015, 12:16 AM   #1
Mazubo
Scooby Newbie
 
Member#: 349900
Join Date: Mar 2013
Default Attacking aftermarket exhaust!

Hi all,
I have an 04 Forester XT, and am looking to upgrade the exhaust. Also looking for a bit of that Subie Rumble! (Not wanting it loud, however a bit of growl when you hop on it..) Upon researching the forums here, on Nasioc, Subaru Forester forums, I've broken it down to these steps. Please tell me if I'm off on something, or suggestions that might help.

1 I understand that it's best to do the exhaust upgrade all at the same time, including Cobb AP so as not to put excess stress onto the engine

2 considering Perrin, Cobb, or similar downpipe, and marrying it to a similar year 03-07 sti catback exhaust, and using kartboy extra long exhaust hangers for better fitment..

3 should I stick with stock sti muffler, or something less restrictive?

***I'm wanting to keep stock air intake with k&n air filter, unless there is something else I can do besides CAI,

Do a stage 1? Tune with Cobb accessport V3.

The only other questions I have would be: what does the uppipe do for me, is it necessary? And would it be ok to do a turbo upgrade down the road, even though the Cobb AP tune is done prior?

Thanks a lot guys for any help here!
* Registered users of the site do not see these ads.
Mazubo is online now   Reply With Quote
Sponsored Links
* Registered users of the site do not see these ads.
Old 09-15-2015, 10:36 AM   #2
playslikepage71
Scooby Newbie
 
Member#: 395882
Join Date: Jul 2014
Chapter/Region: MWSOC
Location: GR, Michigan
Vehicle:
2016 WRX
DGM

Default

You sir, have some reading to do. I'll give you some basic answers to help you figure out what to read.

1 - Not necessary. Plenty of people run stock catbacks with zero issues, even with upgraded downpipes, turbos, etc.

2 - All of the downpipes are going to perform roughly the same

3 - STI mufflers are pretty good for a bolt on upgrade car, if you like the noise go for it

CAI - You could get a short ram like the Cobb SF intake, but you'll definitely want the box to keep intake air temps down

tune - You'll have to use the stage 2 maps if you have a downpipe installed. Stage one is just a fix for the crappy factory tune

up pipe - Not necessary, but makes a huge difference if you have a catted up pipe. It removes a lot of the restriction so it will help the turbo spool up faster and maintain boost further into the RPM range.

turbo upgrade - Turbo upgrades can be iffy on stock blocks, but if you're willing to take the hit in durability, go for it. You'll need a pro tune if you upgrade the turbo, regardless. There are a lot of other things you should do before the turbo though (TMIC, fuel pump/injectors, EBCS, etc.) to properly support the engine and minimize the risk of blowing it up (even with the stock turbo).
playslikepage71 is offline   Reply With Quote
Old 09-15-2015, 09:56 PM   #3
Mazubo
Scooby Newbie
 
Member#: 349900
Join Date: Mar 2013
Default

Quote:
Originally Posted by playslikepage71 View Post
You sir, have some reading to do. I'll give you some basic answers to help you figure out what to read.

1 - Not necessary. Plenty of people run stock catbacks with zero issues, even with upgraded downpipes, turbos, etc.

2 - All of the downpipes are going to perform roughly the same

3 - STI mufflers are pretty good for a bolt on upgrade car, if you like the noise go for it

CAI - You could get a short ram like the Cobb SF intake, but you'll definitely want the box to keep intake air temps down

tune - You'll have to use the stage 2 maps if you have a downpipe installed. Stage one is just a fix for the crappy factory tune

up pipe - Not necessary, but makes a huge difference if you have a catted up pipe. It removes a lot of the restriction so it will help the turbo spool up faster and maintain boost further into the RPM range.

turbo upgrade - Turbo upgrades can be iffy on stock blocks, but if you're willing to take the hit in durability, go for it. You'll need a pro tune if you upgrade the turbo, regardless. There are a lot of other things you should do before the turbo though (TMIC, fuel pump/injectors, EBCS, etc.) to properly support the engine and minimize the risk of blowing it up (even with the stock turbo).
Thank you very much for the thorough reply! You have put every question I had to rest. Much appreciated!
Mazubo is online now   Reply With Quote
Old 09-16-2015, 07:39 AM   #4
HinshawWRX
Medium Frank
Moderator
 
Member#: 140114
Join Date: Feb 2007
Chapter/Region: MAIC
Location: Common Sense, VA
Vehicle:
2014 Porsche
GT3 (Currently on Fire)

Default

http://forums.nasioc.com/forums/showthread.php?t=533787

Read that 10 times before spending ANY money.
HinshawWRX 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 11:57 PM.


Powered by vBulletin® Version 3.7.0
Copyright ©2000 - 2016, Jelsoft Enterprises Ltd.
Powered by Searchlight © 2016 Axivo Inc.
Copyright ©1999 - 2016, North American Subaru Impreza Owners Club, Inc.