Welcome to the North American Subaru Impreza Owners Club Monday August 20, 2018
Home Forums WikiNASIOC Products Store Modifications Upgrade Garage
Go Back   NASIOC > NASIOC Technical > Subaru Conversions

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. 
Thread Tools Display Modes
Old 12-18-2010, 10:26 PM   #1
Scooby Newbie
Member#: 267527
Join Date: Dec 2010
04 wrx sti

Default Phase 2 2.5L into an STI swap!

Hey guys, I am a newbie to the forums and was hoping that a few of you could give me some advice and input. I own a car lot and recently purchased an sti at auction that does not have an engine and is also missing the ecu and turbo parts.

Over the years i have compiled a few engines here and there and happen to have a 2.5L engine thats a phase 2 from either a 99 legacy gt or a 2.5 RS. The engine is built, with arias pistons, manly arms, etc. good for 8:1 compression. My hopes were that i could throw this into the STI and get to keep it for myself instead of having to part it out and make some money.

So my question is, will this 2.5 fit into the 2005 sti that i recently purchased? Will it line up right with the stock transmission? Any of the engine accessories need drastic alterations? Any advice would be great.
Im debating on whether or not this is a likely possibilty or am i better off buying an actual sti motor. Hopefully i can use this engine and then buy the turbo components seperately and save myself about 2-2.5 grand and have a built engine in it .

I am guessing the engine will fit, as ive read of people putting sti motors into other subarus, but im just trying to get a feel for what i am getting myself into.

Thanks in advance for any suggestions and advice!
* Registered users of the site do not see these ads.
tksautos is offline   Reply With Quote
Sponsored Links
* Registered users of the site do not see these ads.
Old 12-19-2010, 12:44 PM   #2
Scooby Guru
Member#: 5218
Join Date: Mar 2001
Chapter/Region: MWSOC
Location: SAUL'S Motorsports
96L Most Over-
Developed Beater


From what I've gathered, issues you will run into are the up pipe clearing the corner of the passenger cylinder head and the lack of AVCS function on that phase II SOHC EJ25. Ideally, you'd source a set of STi heads to bolt onto the block and cure those 2 issues in one step.

Mechanically, everything bolts up, use the STi flywheel and clutch. Use the STi intake manifold and engine harness, add a 2nd block vent and drop it in.

Storm is offline   Reply With Quote
Old 12-19-2010, 06:06 PM   #3
Scooby Specialist
Member#: 152984
Join Date: Jul 2007
Chapter/Region: SCIC
Location: san diego
2004 jewbaru
jewbuilt, polish tuned


its more work to make it run poorly, than to make money selling it all
feint05 is offline   Reply With Quote
Old 12-20-2010, 09:21 AM   #4
NASIOC Supporter
Member#: 177
Join Date: Aug 1999
Chapter/Region: NWIC
Location: Austin, Texas, USA
The 93 W/EJ20K-sold
Subaru-less :(


quick list of why not:
no holes to mount coil on plug
no oil return
different pick up pattern on the cam trigger
Jaxx is offline   Reply With Quote

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
who gas swapped a 2.5L into an L or OBS? OSUBeaver Subaru Conversions 33 08-26-2010 06:37 PM
Planning an STI swap into 06 2.5i SubiFTW Subaru Conversions 5 09-30-2007 02:49 PM
Impreza 2.5 into an STi? hatch'd06 Subaru Conversions 13 11-27-2006 09:27 PM
dropping in a 2.2 or a 2.5 ltr into an older impreza with a 1.8 BeAn Normally Aspirated Powertrain 2 03-22-2001 12:18 AM

All times are GMT -4. The time now is 11:00 AM.

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.