Welcome to the North American Subaru Impreza Owners Club Tuesday January 27, 2015
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 > 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 10-17-2004, 09:47 PM   #1
vhalin
Scooby Specialist
 
Member#: 21445
Join Date: Jul 2002
Location: bay area, ca
Vehicle:
08 STI
silver

Question Forester XT engine vs WRX STi engine

Hi, I drive a WRX as a Daily Driver and an Eclipse GST as my enthuisiast car (only because the parts are cheaper, AWD > FWD) Now I'm selling both to get a new car. Mabye an EVO? Mabye an STI?

Im in a situation where I want a fast car but the person helping me buy it (my mother) wants me to have a safe car. She thinks the WRX STi is not safe enough, she wants me to get an SUV (Ughhh ) She doesnt mind me having a fast car, my last car was a modded GST so thats not a problem. Its just the part about being Safe. She demands I get an SUV. I read up on subaru of americas website and they both have a 2.5L turbocharged engine but one makes 300hp and the other makes 210. Then on In this forum we discuss both engines as if they were the same.

1. What are the differences between the two engines?
2. Hows the availibility on XT parts? Are they hard to find ?
3. What is the weight differences of these two cars?

Ive been into modding cars for a while and I always wanted to have a sleeper and I think the XT would be a perfect car to do it in.

Thanks
Matt
* Registered users of the site do not see these ads.
vhalin is offline   Reply With Quote
Old 10-17-2004, 10:53 PM   #2
SolbergWRCfan
Scooby Newbie
 
Member#: 56229
Join Date: Feb 2004
Chapter/Region: MWSOC
Location: Hudsonville, Michigan
Vehicle:
2001 Subaru Forester
Blue Ridge Pearl

Default

Quote:
Originally Posted by Vhalin
Hi, I drive a WRX as a Daily Driver and an Eclipse GST as my enthuisiast car (only because the parts are cheaper, AWD > FWD) Now I'm selling both to get a new car. Mabye an EVO? Mabye an STI?

Im in a situation where I want a fast car but the person helping me buy it (my mother) wants me to have a safe car. She thinks the WRX STi is not safe enough, she wants me to get an SUV (Ughhh ) She doesnt mind me having a fast car, my last car was a modded GST so thats not a problem. Its just the part about being Safe. She demands I get an SUV. I read up on subaru of americas website and they both have a 2.5L turbocharged engine but one makes 300hp and the other makes 210. Then on In this forum we discuss both engines as if they were the same.

1. What are the differences between the two engines?
2. Hows the availibility on XT parts? Are they hard to find ?
3. What is the weight differences of these two cars?

Ive been into modding cars for a while and I always wanted to have a sleeper and I think the XT would be a perfect car to do it in.

Thanks
Matt
Forrester: No AVCS, smaller turbo, less forged internals, weaker 5spd tranny, slightly heavier, similar modification potential.

The STi is no less safe than the Forrester and SUVs suck. Unless I needed to haul more things than the STi could hold I don't think there is any reason I would buy a Forrester XT.

Jon
SolbergWRCfan is offline   Reply With Quote
Old 10-17-2004, 11:42 PM   #3
nathansvt
Scooby Specialist
 
Member#: 28650
Join Date: Nov 2002
Chapter/Region: TXIC
Default

The STi and the Forester use the same shortblock, and thus the same internals. The STi also has great crash-test ratings, although I suppose the added weight of the XT would help if you're hit by another large vehicle. I've got an STi and think that based on your past cars you'd likely be happier with the STi. But, the XT is cheaper and if your mom's going to be helping out it'd probably be nice to save her some $$. Also, they do make amazing sleepers. A set of springs, some nice rims, and a dark tint job makes it a mean looking car. FWIW, have you looked at the legacy GT?
nathansvt is offline   Reply With Quote
Old 10-17-2004, 11:44 PM   #4
supermarkus
Scooby Guru
 
Member#: 6971
Join Date: May 2001
Location: Edmonds, Washington, USA
Vehicle:
2008 WRX STi
SSM

Default

Quote:
Originally Posted by SolbergWRCfan
Forrester: No AVCS, smaller turbo, less forged internals

Jon

Taken from Subaru's website:
Quote:
2.5-liter DOHC intercooled, turbocharged aluminum-alloy 16-valve 4-cylinder horizontally opposed Subaru Boxer engine with Active Valve Control System (AVCS). Iridium spark plugs. Sodium-filled exhaust valves.
They could be wrong. A subaru mechanic I talked to yesterday said they were the same long block, just different EM, IC, turbo, and intake color.
supermarkus is offline   Reply With Quote
Old 10-17-2004, 11:54 PM   #5
joebud
Scooby Newbie
 
Member#: 55089
Join Date: Feb 2004
Chapter/Region: SWIC
Location: GoodSpeed Performance
Default

Forrester uses AVCS
joebud is offline   Reply With Quote
Old 10-18-2004, 12:14 AM   #6
fogdor
Scooby Specialist
 
Member#: 45726
Join Date: Oct 2003
Vehicle:
2007 Mazdaspeed3
Cosmic Blue

Default

SUV's are not safe vehicles, get your friend to look at the facts. The fact is the WRX/STi and Forrester are all pretty much the same chassis and are all VERY chunky (3300+ lbs) and safe from a structural stiffness point of view.
fogdor is offline   Reply With Quote
Old 10-18-2004, 12:46 AM   #7
speedypete
Scooby Newbie
 
Member#: 62012
Join Date: May 2004
Location: upstate NY
Vehicle:
2004 FXT 5speed
Cobb stage 2

Default

Basically the same engine except the Sti has a bigger turbo and intercooler. As far as weight goes the forester weighs 3225 lbs and the STI 3298 lbs.
As far as parts, not a problem...there are a ton of mods available.

BTW...the Forester isn't a suv. SOA uses that as marketing. Think of it as a tall Impreza wagon.
speedypete is offline   Reply With Quote
Old 10-18-2004, 12:49 AM   #8
vhalin
Scooby Specialist
 
Member#: 21445
Join Date: Jul 2002
Location: bay area, ca
Vehicle:
08 STI
silver

Default

Quote:
Originally Posted by SolbergWRCfan
Forrester: No AVCS, smaller turbo, less forged internals, weaker 5spd tranny, slightly heavier, similar modification potential.

The STi is no less safe than the Forrester and SUVs suck. Unless I needed to haul more things than the STi could hold I don't think there is any reason I would buy a Forrester XT.

Jon
What kind of turbo is on the forrester XT and how does it differ than the STi Turbo? Also what kind of potential is there to get a bigger turbo?
Im looking into something like
intake, exhaust, downpipe, uppipe, fuel pump, injectors, s-afc, mbc, front mount, exhaust manifold, o2 sensor housing

keep in mind i have yet to do a single mod to my WRX. Im living in the DSM world right now.

let me know what you guys think?

EDIT: my goals are to make STi numbers from the sound of things i need a bigger turbo but i dont know what kind of supporting mods ill need to do that.

Last edited by Vhalin; 10-18-2004 at 01:01 AM.
vhalin is offline   Reply With Quote
Old 10-18-2004, 01:18 AM   #9
Oi8ur5.0
Scooby Specialist
 
Member#: 28910
Join Date: Nov 2002
Chapter/Region: MAIC
Location: Frederick, MD
Vehicle:
2013 REX
DARK GREY

Default

FXT is the best bang for the buck going. Period.

The engine is exactly the same. Injectors,AVCS etc. You are not paying for all the typical parts on an STI that would be upgraded for BIG power. e.g. Turbo,IC (allthough the STI ic seems like plenty for a top mount). FXT has a catted up pipe as where the STI does not.

Nathen from TXS stated that the UTEC was not limted to 7 K on the FXT ECU as it is on the STI ECU. So add that one to the plus column.

I'm 97% sure that the tranny is the previous version STI 5 spd. It is heads and tails better than a WRX 5 speed.....and better for straight line then the STI 6 spd gearing wise.(Allthough...I think the 6 spd is still stronger) It feels great.

I think the ride height is a very big factor in side impact worthiness...and that's one of the reason's the Forester in general is rated so high. But all of them are pretty good. While stopped in my REX......I was hit from behind by a guy doing 80+ MPH. The rex is gone....but I'm still here....and I pay a bunch more attention to crash ratings these days.

Anyways....dig this link to some pics of my black FXT with 17" SSR's..and an STI scoop.

http://www.subaruforester.com/viewtopic.php?t=5925


If you need handeling and as six spd....then you need an STI.

If you could find some fun with a sleeper Forester from Hell....it's a cheap option.

I'm a serious home depot, mountain bike, guitar's and amp's haulin nut. I can do that and get my Torque jones goin all at the same time.

(wipes tears away)

Oh.....and the 210 hp rating on the FXT is pure fiction. 240+ I'd say.

Last edited by Oi8ur5.0; 10-18-2004 at 01:39 AM.
Oi8ur5.0 is offline   Reply With Quote
Old 10-18-2004, 01:38 AM   #10
Oi8ur5.0
Scooby Specialist
 
Member#: 28910
Join Date: Nov 2002
Chapter/Region: MAIC
Location: Frederick, MD
Vehicle:
2013 REX
DARK GREY

Default

"" my goals are to make STi numbers from the sound of things i need a bigger turbo but i dont know what kind of supporting mods ill need to do that.""



Stock Forester Turbo is the td04...exactly what's in a stock WRX.

Any mods available for the STI, fit the FXT...turbo's and all. Even STI suspension mods fit the FXT.

IF you just want STI type power...then buy a VF34 turbo from the STI guys who are upgrading. Replace your upipe...get a UTEC and exhaust...maybe a Top mount intercooler....and you'll eat stock STI's in the straights....big time.

Personally, I like broken drivetrain.....so I'm going for a Super zilla and the supporting cast.
Oi8ur5.0 is offline   Reply With Quote
Old 10-18-2004, 04:17 AM   #11
vhalin
Scooby Specialist
 
Member#: 21445
Join Date: Jul 2002
Location: bay area, ca
Vehicle:
08 STI
silver

Default

is an FMIC a good idea for a FXT? after researching im thinking; sti turbo, upgraded intercooler(not sure if FMIC or TMIC), downpipe, uppipe, exhaust, ebc and intake. how does that sound?

also, where is/are some good places/sites to get FXT parts from?
vhalin is offline   Reply With Quote
Old 10-18-2004, 08:11 AM   #12
fmowry
Scooby Specialist
 
Member#: 54604
Join Date: Feb 2004
Chapter/Region: MAIC
Location: Severn, MD
Vehicle:
2004 FXT
Cayenne Red (sold)

Default

FXT bumper won't easily allow a FMIC. Plenty of good topmount upgrades unless you're gonna go with a monster turbo.

Frank
fmowry is offline   Reply With Quote
Old 10-18-2004, 09:52 AM   #13
DRNWAGN
Scooby Specialist
 
Member#: 44255
Join Date: Sep 2003
Chapter/Region: MAIC
Location: G.Burg / NIH, MD
Vehicle:
10 Scion TC

Default

Ok, I have an 04 FXT. Just finished some big upgrades! STI ecu, sti turbo (vf39), Perrin tmic, silicon hoses, Cusco catch can, Borla header, PDE up pipe, DN Performance turbo back 3" exhaust, Sti suspension, Sti tires, 17" rims (tsw), Cobb ss, Txs bov, txs intake, Greddy Gauges, tower braces and H brace.

So, with all of that said, it rolls with Sti's in stock trim if you will. It is quite fast and still has room for the family. The things you will not get are the nice bbs rims, larger brakes, cool looking interior (big debate as to whether or not the seats are nicer), sedan look verses wagon. You will have to do quite a bit of work to get the performance of the sti out of the fxt. But you can pick up most of the stuff fairly cheap if you look around. The ecu cost me about $500 shipped but others have picked them up for as little as $300.

You can check out www.subaruforester.com for more info on some of the upgrades that Forester guys have done. Basically, most of the stuff for the sti will fit the fxt. But the fmic is tricky due to the styling of the bumper and most exhausts for the wrx/sti are too short and need to be reworked by a local muffler shop.

If it was not for my wife complaining I would have bought the sti. I can only imagine what my sti would have been like with the same amount of money dumped in to it that I have put into the fxt. If I could do it again I would have an sti sitting in the driveway.

Maybe you need to print out some crash test information for your mom! That may help your situation some.
DRNWAGN is offline   Reply With Quote
Old 10-18-2004, 10:38 AM   #14
bluesubie
Scooby Guru
 
Member#: 767
Join Date: Jan 2000
Chapter/Region: Tri-State
Location: N.J.
Vehicle:
04 FXT

Default

Since the others straightened the facts out on the engine, here are some crash test links for you.

Forester IIHS results
Impreza IIHS results
Forester NHTSA results
Impreza wagon NHTSA results

-Dennis
bluesubie is offline   Reply With Quote
Old 10-18-2004, 11:27 AM   #15
supermarkus
Scooby Guru
 
Member#: 6971
Join Date: May 2001
Location: Edmonds, Washington, USA
Vehicle:
2008 WRX STi
SSM

Default

Quote:
Originally Posted by Oi8ur5.0
IF you just want STI type power...then buy a VF34 turbo from the STI guys who are upgrading.

FWIW, I don't have a VF34, I'm pretty sure "STi guys" all have VF39s as the stock turbos here in North America.
supermarkus is offline   Reply With Quote
Old 10-18-2004, 12:16 PM   #16
xspeedrj
Scooby Newbie
 
Member#: 34710
Join Date: Apr 2003
Location: Milwaukee, WI
Vehicle:
2004 Forester XT 5MT
Java Black

Default

FYI

Don't get hung up on the 210 HP rating for the FXT. Not sure many people believe that noting the dynos that have been done so far (compared to the WRX and STI).

Read somewhere that a Subaru guy in Canada admitted the car comes with 250 HP like the other detuned 2.5L Subbies. Not gospel, but I would tend to believe it.
xspeedrj is offline   Reply With Quote
Old 10-18-2004, 12:25 PM   #17
Oi8ur5.0
Scooby Specialist
 
Member#: 28910
Join Date: Nov 2002
Chapter/Region: MAIC
Location: Frederick, MD
Vehicle:
2013 REX
DARK GREY

Default

Quote:
Originally Posted by supermarkus
FWIW, I don't have a VF34, I'm pretty sure "STi guys" all have VF39s as the stock turbos here in North America.

The way I write (and add), 4' and 9's are fluid substitutions for one another.


DRNWAGN: Are you running the stock STI tune with that ecu ? I'm curious as to why you made that ECU swap. Further EM plans ?
Oi8ur5.0 is offline   Reply With Quote
Old 10-18-2004, 12:27 PM   #18
maestro
Scooby Specialist
 
Member#: 53021
Join Date: Jan 2004
Chapter/Region: SCIC
Location: West Hollywood
Vehicle:
'04 Forester - sold
'72 Datsun 240Z

Default

Quote:
Originally Posted by SolbergWRCfan
Forrester: No AVCS, smaller turbo, less forged internals, weaker 5spd tranny, slightly heavier, similar modification potential.

The STi is no less safe than the Forrester and SUVs suck. Unless I needed to haul more things than the STi could hold I don't think there is any reason I would buy a Forrester XT.

Jon

OMG, so wrong... Do the proper research before spreading misinformation.

Again:

Forester (with one R )
- AVCS - same as STi
- internals - same as STi
- 5spd - stronger than WRX, but yes, weaker than STi
- weight - lighter than the STi
- it's not an SUV

The ONLY differences enginewise are 1) Turbo, 2) up-pipe, 3)ecu, 4)intercooler.

I just replaced the aforementioned 4 items last night plus some other goodies, and my Forester is now faster than a stock STi. And I can haul more stuff too. Ha.
maestro is offline   Reply With Quote
Old 10-20-2004, 11:52 AM   #19
vhalin
Scooby Specialist
 
Member#: 21445
Join Date: Jul 2002
Location: bay area, ca
Vehicle:
08 STI
silver

Default

the XT is really lighter than the STi? what makes this possible?
vhalin is offline   Reply With Quote
Old 10-20-2004, 12:06 PM   #20
supermarkus
Scooby Guru
 
Member#: 6971
Join Date: May 2001
Location: Edmonds, Washington, USA
Vehicle:
2008 WRX STi
SSM

Default

The 6 speed tranny is like 80 lbs heavier if memory serves me correctly. And those 17" rims and big rotors certainly add some weight.
supermarkus is offline   Reply With Quote
Old 10-20-2004, 12:11 PM   #21
vhalin
Scooby Specialist
 
Member#: 21445
Join Date: Jul 2002
Location: bay area, ca
Vehicle:
08 STI
silver

Default

I know my WRX has a carbon fibre hood does the XT have a CF hood too? My wrx doors are incredibly light. i could close them with my eyelids alone, can i expect the same from an XT?
vhalin is offline   Reply With Quote
Old 10-20-2004, 12:20 PM   #22
Jitenshakun
Scooby Specialist
 
Member#: 61586
Join Date: May 2004
Chapter/Region: W. Canada
Location: Alberta
Vehicle:
2005 STi
WI and all the goodies

Default

The STi frame has been designed to acheive the same results as a roll cage, unlike any SUV. The only reason SUVs are "safer" in accidents is becasue when they hit a smaller car, i.e. a civic, they walk away with minor fender damage and the guy in the civic rolls away on a stretcher. If you check the crash testing on SUVs (i.e SUV vs. concrete wall) they don't fare so hot.

I realize this doens't address your performance questions but maybe your mom needs some new information.

You'll be very disappointed if you had the option to get an STi and went with a Forrester instead.

-J
Jitenshakun is offline   Reply With Quote
Old 10-20-2004, 12:39 PM   #23
Oi8ur5.0
Scooby Specialist
 
Member#: 28910
Join Date: Nov 2002
Chapter/Region: MAIC
Location: Frederick, MD
Vehicle:
2013 REX
DARK GREY

Default

Quote:
Originally Posted by Vhalin
I know my WRX has a carbon fibre hood does the XT have a CF hood too? My wrx doors are incredibly light. i could close them with my eyelids alone, can i expect the same from an XT?

Your stock WRX hood is aluminum...not CF. I think the FXT has an aluminum hood as well....but I'm not sure. It feels light though.

Those WRX doors feel light when you have the added value of four case hardened bolts holding it up. Take those bolts out...and you best get your toes out of the way. They appear light..because the engineering is pretty darn good.
Oi8ur5.0 is offline   Reply With Quote
Old 10-20-2004, 02:18 PM   #24
nathansvt
Scooby Specialist
 
Member#: 28650
Join Date: Nov 2002
Chapter/Region: TXIC
Default

Quote:
Originally Posted by Jitenshakun
The STi frame has been designed to acheive the same results as a roll cage, unlike any SUV. -J


The STi is on the same unibody as every other impreza. I know they're good in crash tests (as is the XT), but the same as a roll cage? Don't think so.
nathansvt is offline   Reply With Quote
Old 10-20-2004, 02:28 PM   #25
zmw
Scooby Specialist
 
Member#: 13181
Join Date: Dec 2001
Chapter/Region: TXIC
Location: The Schlit
Vehicle:
97 Supra
FAST

Default

Jitenshakun: that may be the most assinine thing I have ever seen someone post... the STI and forester and every other impreza line share the same unibody construction - your statement of it being built like a roll cage is retarded at best and completely and totally uninformed at worst.... although I could be wrong, maybe you should call the subaru WRC team and suggest the remove the roll cage to save a lot of weight?....

-Z
zmw 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
04 STI Engine vs 05 STI Engine Heater Guy Proven Power Bragging 11 08-20-2009 07:13 PM
06 WRX Engine vs 06 STi Engine cwepruk Factory 2.5L Turbo Powertrain (EJ Series Factory 2.5L Turbo) 13 01-03-2008 02:11 PM
04 usdm wrx engine vs v4 sti engine? d1giPhux Subaru Conversions 7 11-23-2007 04:17 PM
G35 engine Knock vs WRX STi engine Knock... BBBsti LTD General Community 6 03-21-2007 02:40 AM
WTB: Forester XT or Impreza WRX STi gas pedal Slack Private 'Wanted' Classifieds 0 05-03-2005 08:41 PM


All times are GMT -4. The time now is 05:53 PM.


Powered by vBulletin® Version 3.7.0
Copyright ©2000 - 2015, Jelsoft Enterprises Ltd.
Powered by Searchlight © 2015 Axivo Inc.
Copyright ©1999 - 2014, North American Subaru Impreza Owners Club, Inc.