Welcome to the North American Subaru Impreza Owners Club Tuesday September 16, 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 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.
* Registered users of the site do not see these ads.
Reply
 
Thread Tools Display Modes
Old 07-15-2004, 07:49 AM   #1
Rainierez
Scooby Newbie
 
Member#: 66332
Join Date: Jul 2004
Location: Indianapolis, IN
Vehicle:
2000 Impreza RS
Silver

Question Engine build up questions

Ok I'm kinda new in the scooby world but it seems I have alot of options for turboing my 2.5 and I wanna throw up a "pros and cons" thread. As it stands now I have the SOHC EJ25 in my car. I don't want that turboed cause of the hih compression rate. I have a spare EJ25 DOHC engine in my shop. So I Suppose my question is what would go better, the STI short block with the SOHC heads or DOHC? Or even the EJ22T shortblock with either set of heads. I have follow up questions based on all 4 answers E-mail me if you have pics of a certian setup or would like to buy the one of the two spare EJ25 blocks off of me.

Chris C.
Rainierez is offline   Reply With Quote
Old 07-15-2004, 08:02 AM   #2
totoherbs
Scooby Guru
 
Member#: 7321
Join Date: Jun 2001
Chapter/Region: NESIC
Location: waltham, ma
Vehicle:
.... 122 IggPoints
Work... ahhh... so tired.

Default

If you have any ej22 questions this should help... http://forums.nasioc.com/forums/show...highlight=ej22

SOHC would flow better down low and DOHC up top, but either would work...
totoherbs is offline   Reply With Quote
Old 07-15-2004, 01:39 PM   #3
IllNastyImpreza
Scooby Guru
 
Member#: 36333
Join Date: May 2003
Chapter/Region: NESIC
Location: East Kingston NH
Vehicle:
DIY project: life
I need more TIME!

Default turbo

Personaly I'm going with the ej22t on my stock 98 DOHC heads, basicly NO wiring

the sti shortblock, even though semi closed deck, is still VERRY open. The cylinder walls are verry thin compared to the ej22t. If you someday want to upgrade past 400HP, then I would stay away from the ej257.

as far as heads go, duel overhead cams are always better than single. But if you have the SOHC mounted up on the car already then it would be pretty much plug and play. in the end it all comes down to how much total power you are looking for and just how involved you want to become in your project.
IllNastyImpreza is offline   Reply With Quote
Old 07-15-2004, 07:49 PM   #4
Rainierez
Scooby Newbie
 
Member#: 66332
Join Date: Jul 2004
Location: Indianapolis, IN
Vehicle:
2000 Impreza RS
Silver

Default

Well i was thinking the ej22t as well I have the DOHC sitting around and would probly put them on the EJ22t block. A few questions there what do i have to do to make the EJ25 DOHC fit and work eff. witht he 22t block? Also what kinda wiring will i have to change, I'm an electronic repair tech so no of that scares me just want to know before i jump head long into it. Side question would finding a EJ22T ECU be a good thing for the engine esp. once it is turboed or will a stand alone or piggy back work better??
Rainierez is offline   Reply With Quote
Old 07-15-2004, 08:28 PM   #5
subiekid
Scooby Guru
 
Member#: 25516
Join Date: Oct 2002
Chapter/Region: NWIC
Location: Send help, stuck in internet!
Vehicle:
1995 Legacy TURBO!!!
EJ22T/TEC3 & '12 Civic

Default

I have an ej22T swap in my car and I am looking at putting some 98 DOHC heads onto my block. The only thing I am woried about is the fact that the DOHCs blow head gaskets all the time.
subiekid is offline   Reply With Quote
Old 07-15-2004, 09:22 PM   #6
kaos200
Scooby Guru
 
Member#: 2692
Join Date: Oct 2000
Chapter/Region: SCIC
Location: SoCal
Default

Quote:
Originally posted by IllNastyImpreza

the sti shortblock, even though semi closed deck, is still VERRY open. The cylinder walls are verry thin compared to the ej22t. If you someday want to upgrade past 400HP, then I would stay away from the ej257.
there are plenty of people pushing past 400 hp on the 257, so I dont see the basis for that statement
kaos200 is offline   Reply With Quote
Old 07-15-2004, 09:23 PM   #7
totoherbs
Scooby Guru
 
Member#: 7321
Join Date: Jun 2001
Chapter/Region: NESIC
Location: waltham, ma
Vehicle:
.... 122 IggPoints
Work... ahhh... so tired.

Default

Quote:
Originally posted by kaos200
there are plenty of people pushing past 400 hp on the 257, so I dont see the basis for that statement
Well one persons 400 is anothers 300 so... I think what he means is if your looking for 400 and over go with a built block. A sock subaru block will hold 400-450 but not for very long.
totoherbs is offline   Reply With Quote
Old 07-16-2004, 06:58 PM   #8
IllNastyImpreza
Scooby Guru
 
Member#: 36333
Join Date: May 2003
Chapter/Region: NESIC
Location: East Kingston NH
Vehicle:
DIY project: life
I need more TIME!

Default

Quote:
Originally posted by kaos200
there are plenty of people pushing past 400 hp on the 257, so I dont see the basis for that statement
this has been discussed before when people questioned the ej25's open deck nature. It doesnt come down to how much peak horsepower and boost it can hold at one time, But rather for how long you can punish the relitavely weakly reinforced walls of the block.
If I could figure out how to post picstures I could post the ej25 vs ej22t vs ej257. can someone help me out?

It seems that the STI block, as well as the ej25 have ALOT of unreinforced area behind the cylinder walls. All this space is the reason you can only run so much boost for so long before those nice circular cylinder walls become nice oval cylinder walls. Note that the ej22t is almost completly closed in...thats a real block right there
IllNastyImpreza is offline   Reply With Quote
Old 07-16-2004, 09:34 PM   #9
Rainierez
Scooby Newbie
 
Member#: 66332
Join Date: Jul 2004
Location: Indianapolis, IN
Vehicle:
2000 Impreza RS
Silver

Default

I have been leaning that way (for the ej22) but what to do about the heads??? Should i have them machined at all. I hear in the stock formt hey push the compresion rate even lower under 8:1??? is this true and what can i do about that???
Rainierez is offline   Reply With Quote
Old 07-16-2004, 10:38 PM   #10
totoherbs
Scooby Guru
 
Member#: 7321
Join Date: Jun 2001
Chapter/Region: NESIC
Location: waltham, ma
Vehicle:
.... 122 IggPoints
Work... ahhh... so tired.

Default

Quote:
Originally posted by IllNastyImpreza
this has been discussed before when people questioned the ej25's open deck nature. It doesnt come down to how much peak horsepower and boost it can hold at one time, But rather for how long you can punish the relitavely weakly reinforced walls of the block.
If I could figure out how to post picstures I could post the ej25 vs ej22t vs ej257. can someone help me out?

It seems that the STI block, as well as the ej25 have ALOT of unreinforced area behind the cylinder walls. All this space is the reason you can only run so much boost for so long before those nice circular cylinder walls become nice oval cylinder walls. Note that the ej22t is almost completly closed in...thats a real block right there
Ya, but you putting way to much on the closed deck aspect of the block. Its not that important. The problem with the 257 is its a lose motor(no very well balance from the factory), pistons are heavy, and the walls are thiner then most subaru blocks. http://forums.nasioc.com/forums/show...hreadid=536442

But its like any stock subaru block will be fine in the 350-400 whp range on the right turbo with out problem. The 2.5L is just for people who like low end pull and mid 20 boost levels where as the 2.0 is for people who like to rev and boost high. The 2.2 is a great half and half more low end pull and it will hold the boost.
totoherbs 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
engine build up questions 03 RS Built Motor Discussion 0 08-22-2006 07:08 PM
engine build up idodsick Newbies & FAQs 1 04-05-2004 01:54 AM
Project WRX Engine Build Up vividracing Member's Car Gallery 9 06-18-2003 07:06 PM
Is cobb a good choice for an engine build-up? Szm426 Factory 2.0L Turbo Powertrain 7 11-30-2002 12:32 AM
anyone have one of those dyno or engine build up software kits? funscooby Motorsports 0 01-17-2002 01:44 AM


All times are GMT -4. The time now is 11:31 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.