Welcome to the North American Subaru Impreza Owners Club Monday March 18, 2024
Home Forums Images WikiNASIOC Products Store Modifications Upgrade Garage
NASIOC
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.







* As an Amazon Associate I earn from qualifying purchases. 
* Registered users of the site do not see these ads. 
Reply
 
Thread Tools Display Modes
Old 06-25-2003, 11:08 PM   #1
Dr Ken
Scooby Specialist
 
Member#: 5885
Join Date: Apr 2001
Chapter/Region: NWIC
Location: Portland Oregon
Vehicle:
2000 RS (GME)
SilvAr

Default 2.25" vs 2.5" exhaust question

Hello, I've not posted in this forum before and am really very new to FI stuff.
I've ordered a TWE header and cat to complement my brullen cat back, all 2.25". If I were to add a (AVO?) turbo, how much performance would you think I'd be loosing by keeping this diameter piping instead of going up to 2.5"???
THanks,
* Registered users of the site do not see these ads.
Dr Ken is offline   Reply With Quote
Sponsored Links
* Registered users of the site do not see these ads.
Old 06-26-2003, 12:01 AM   #2
Midwayman
Scooby Specialist
 
Member#: 1997
Join Date: Jul 2000
Chapter/Region: MWSOC
Location: Des Plaines, IL
Vehicle:
2006 Acura TL 6spd
STMGM6 alumni

Default

Depends on how much power you're running. 2.5" is good upto about 300bhp. so 2.25".... probably good enough for a 5psi kit without much loss. Bigger is always better with the turbo.
Midwayman is offline   Reply With Quote
Old 06-26-2003, 01:16 AM   #3
Eric SS
Sooby Guru
 
Member#: 1914
Join Date: Jul 2000
Chapter/Region: SWIC
Location: 2014 Q60S, 2016 Chevy SS
Vehicle:
2000 2.5RS w/ EJ22T
swap and N20. gone. : (

Default

Quote:
Originally posted by Midwayman
Bigger is always better with the turbo.
Yeah. I'm a strong believer that you can never over exhaust a turbo car.
Eric SS is offline   Reply With Quote
Old 06-26-2003, 09:23 AM   #4
DanzBorin
Subaru Bounty Hunter
Moderator
 
Member#: 7131
Join Date: Jun 2001
Chapter/Region: TXIC
Location: Houston - Downtown Julie Brown
Vehicle:
2015 Outback - Croc
Dundee Edition Ice Silver

Default

you will have to lose the headers when you turbo the car...

but yes, 2.5" would be better for boost...
DanzBorin is offline   Reply With Quote
Old 06-26-2003, 11:06 AM   #5
Avenger
Scooby Specialist
 
Member#: 1234
Join Date: Apr 2000
Location: Vancouver, Canada
Vehicle:
2000

Default

Quote:
Originally posted by Eric v5.7 beta


Yeah. I'm a strong believer that you can never over exhaust a turbo car.
Darn.. I knew I should got a 5" exhaust.
I got a 2.5" exhaust and it works fine with 8 psi.
Avenger is offline   Reply With Quote
Old 06-26-2003, 12:57 PM   #6
PHATsuby
Scooby Guru
 
Member#: 13617
Join Date: Dec 2001
Chapter/Region: MWSOC
Location: MN
Vehicle:
2001 Legacy GT back
to stock is a project too

Default

which tech works header did you go with? the super stock one? i was told the super stock is best for turbo applications because the high output headers are tuned more for higher end and can only be taken advantage of if you have a raised rev limit.

i am hoping to get some soon once they find out if their older version will fit an automatic. tell me what you think of it once you get it cause it looks like great craftsmanship.


Quote:
you will have to lose the headers when you turbo the car...
i dont believe so because i was told they bolt up to the factory location so basically any of the aftermarket kits will work with it, which is sweet.

Ben
PHATsuby is offline   Reply With Quote
Old 06-26-2003, 02:19 PM   #7
Dr Ken
Scooby Specialist
 
Member#: 5885
Join Date: Apr 2001
Chapter/Region: NWIC
Location: Portland Oregon
Vehicle:
2000 RS (GME)
SilvAr

Default

Yup, Super stock (2.25"), instead of the High output (2.5"). Stock end placement. There are two different ceramic coats available for its mild-steel construction: The shiny, is actually lower temperature rated, for N/A. The dull is for higher temps of forced induction, but more prone to debris chips. I chose the former, but still have time to change to the latter, if going FI with this header seems a reasonable option.

I suppose I'd be obligated to critique these headers once installed, as there are still only a few who have confessed to getting them.

I'm open to suggestions.
Dr Ken 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
2.25" or 2.5" Brullen exhaust? cMags Normally Aspirated Powertrain 2 11-02-2007 12:43 PM
2.25" vs. 2.5" exhaust LandoCommando Normally Aspirated Powertrain 16 05-09-2007 01:26 AM
2.25" to 2.5" axelback? rally_on Normally Aspirated Powertrain 1 11-11-2005 09:06 PM
2", 2.25", and 2.5" blue silicon hose various lengths White 2.5rs Private 'For Sale' Classifieds 4 05-25-2004 05:31 PM
2.25" vs. 2.5" catback piping, how much low end difference? DeusExMachina Normally Aspirated Powertrain 3 04-23-2002 05:31 AM

All times are GMT -4. The time now is 10:45 PM.


Powered by vBulletin® Version 3.7.0
Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.
Powered by Searchlight © 2024 Axivo Inc.
Copyright ©1999 - 2019, North American Subaru Impreza Owners Club, Inc.

As an Amazon Associate I earn from qualifying purchases.

When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission
Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.