Welcome to the North American Subaru Impreza Owners Club Saturday September 20, 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 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 07-09-2013, 10:32 AM   #1
ScoobyDrift
Scooby Newbie
 
Member#: 315446
Join Date: Apr 2012
Location: Trinidad
Vehicle:
2004 Impreza 2.5L

Default Exhaust size?

Advice, i'm running TWE Stage 2 cams and BC 1600 titanium spring and retainer set. I want like to know what size exhaust to use currently i have 2 1/4'' piping but a number of people told me that its too small i should use 2.5''.

Can anyone advise me accordingly.
* Registered users of the site do not see these ads.
ScoobyDrift is offline   Reply With Quote
Old 07-09-2013, 01:10 PM   #2
Masta Splint
Scooby Specialist
 
Member#: 189211
Join Date: Sep 2008
Chapter/Region: SWIC
Location: Peoria & Surprise, Arizona
Vehicle:
2005 18g WRX wagon
Aspen White

Default

Tech. the 1 you have is a good size but you can def go bigger. You can comfortably do a 2.5" exhust and I would not go anything past 3", the 3" may even be a tad bit on the large size since you dont have a turbo.
Masta Splint is offline   Reply With Quote
Old 07-09-2013, 06:15 PM   #3
RaceFaceXC
NASIOC Supporter
 
Member#: 165749
Join Date: Dec 2007
Chapter/Region: South East
Location: stupid Florida
Vehicle:
2007 No YELLING
on the bus!

Default

Quote:
Originally Posted by ScoobyDrift View Post
Advice, i'm running TWE Stage 2 cams and BC 1600 titanium spring and retainer set. I want like to know what size exhaust to use currently i have 2 1/4'' piping but a number of people told me that its too small i should use 2.5''.

Can anyone advise me accordingly.
What header is or will be installed? Match the collector size is usually a sound choice.
RaceFaceXC is offline   Reply With Quote
Old 07-09-2013, 06:23 PM   #4
ScoobyDrift
Scooby Newbie
 
Member#: 315446
Join Date: Apr 2012
Location: Trinidad
Vehicle:
2004 Impreza 2.5L

Default

I'm running brolas unequal headers
ScoobyDrift is offline   Reply With Quote
Old 07-09-2013, 06:35 PM   #5
EdHilario
Scooby Specialist
 
Member#: 137398
Join Date: Jan 2007
Chapter/Region: E. Canada
Location: Toronto
Vehicle:
2004 Impreza 2.5RS
Platinum Silver Metallic

Default

As long as it's a true 2 1/4" diameter piping and mandrel bends, it should be enough. Do you have a catalytic convertor? If so, that's a restriction right there. If you have to do emission tests then leave it on. Otherwise you can replace it with some piping.
EdHilario 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 12:38 PM.


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.