Welcome to the North American Subaru Impreza Owners Club Tuesday May 3, 2016
Home Forums WikiNASIOC Products Store Modifications Upgrade Garage
NASIOC
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. 
Reply
 
Thread Tools Display Modes
Old 02-02-2006, 09:46 PM   #1
jayfressh
Scooby Newbie
 
Member#: 16847
Join Date: Mar 2002
Location: cleveland
Vehicle:
2000 impreza rs 2.5
mach I maroon

Default 2.5 NA heads on EJ20

Purposed swap EJ20 Block with NA 2.5 heads, 2.5 NA manifold and anything else I can salvage from EJ25. Using FMIC so fitting TMIC is not a problem.

I am piecing together my swap. I would like to get a list going so I can start buying parts. Below is a known needed parts list ? Below that are parts I' not sure are needed? Any other parts needed please add!

*I know I will need a custom bend up pipe to clear the cross member.
*Oil pan with return from turbo.
* WRX water pump, thermostat , and inlet neck
*WRX fuel pump
*Upgraded Clutch
*FMIC kit
*Turbo
*Gaskets

Item I'm not sure about and would like opinions on

*Engine management- E-manage possibly use RS ECU?
*WRX Oil Pump?


Any other parts I will need
* Registered users of the site do not see these ads.
jayfressh is offline   Reply With Quote
Sponsored Links
* Registered users of the site do not see these ads.
Old 02-03-2006, 05:19 PM   #2
swapstar
*** Banned ***
 
Member#: 102779
Join Date: Dec 2005
Location: JDM land filling a container
Vehicle:
1998 PM if u need
JDM bits.....

Default

why not just get a stock WRX exhaust manifold (for $40) and the proper turbo X member for $140 or such. cheaper, easier, better than getting ghetto fabulicious stuff made up. bolts right on, and you can source all the parts so easily
swapstar is offline   Reply With Quote
Old 02-06-2006, 08:17 PM   #3
jdmisacult
Scooby Newbie
 
Member#: 100652
Join Date: Nov 2005
Default

I was also curious how the 2.0 block would do with the dohc 2.5 heads. what kind of compretion ratio would we be lookin at?
jdmisacult is offline   Reply With Quote
Old 02-07-2006, 01:53 AM   #4
civic2scooby
Scooby Specialist
 
Member#: 78658
Join Date: Jan 2005
Chapter/Region: MWSOC
Location: East Lansing Michign
Vehicle:
2005 LGT Limited
Black/Black

Default

Quote:
Originally Posted by swapstar
why not just get a stock WRX exhaust manifold (for $40) and the proper turbo X member for $140 or such. cheaper, easier, better than getting ghetto fabulicious stuff made up. bolts right on, and you can source all the parts so easily
well it depends if he is using the 2.5NA SOHC heads or DOHC heads....because the WRX exhaust manifold wont bolt up to the SOHC heads IIRC
civic2scooby is offline   Reply With Quote
Old 02-07-2006, 06:39 AM   #5
swapstar
*** Banned ***
 
Member#: 102779
Join Date: Dec 2005
Location: JDM land filling a container
Vehicle:
1998 PM if u need
JDM bits.....

Default

how do you know? have you tried this or are you blurting out HEARSAY.

they bolt up just fine. all dual port heads have same pattern. you can swap a 1993 ej18 header on a 2005 sti ej257 pair of heads. thats no problem
swapstar is offline   Reply With Quote
Old 02-07-2006, 02:44 PM   #6
Jaxx
NASIOC Supporter
 
Member#: 177
Join Date: Aug 1999
Chapter/Region: NWIC
Location: Austin, Texas, USA
Vehicle:
The 93 W/EJ20K
Series 10 FRS

Default

{blurting}
sohc heads are longer and foul on the uppipe
{/blurting}
Jaxx is offline   Reply With Quote
Old 02-07-2006, 03:34 PM   #7
Matt Monson
Scooby Guru
 
Member#: 832
Join Date: Jan 2000
Chapter/Region: RMIC
Location: Teh Ghetto Garage, CO
Vehicle:
99 2.5RS, '85 911
'73 914 and 2012 BRZ

Default

Quote:
Originally Posted by Jaxx
{blurting}
sohc heads are longer and foul on the uppipe
{/blurting}
classic... and correct...
Matt Monson is offline   Reply With Quote
Old 02-07-2006, 05:06 PM   #8
jayfressh
Scooby Newbie
 
Member#: 16847
Join Date: Mar 2002
Location: cleveland
Vehicle:
2000 impreza rs 2.5
mach I maroon

Default

The heads will fit fine. The compression ratio will be about 8:1 very boost friendly. I'm opting to buy an up pipe from Chad who post here, it will clear the RS cross member.

Swapstar were you refering to bolting WRX exhaust manifold to 2.5 block?
jayfressh is offline   Reply With Quote
Old 02-07-2006, 05:43 PM   #9
swapstar
*** Banned ***
 
Member#: 102779
Join Date: Dec 2005
Location: JDM land filling a container
Vehicle:
1998 PM if u need
JDM bits.....

Default

exhaust manifold bolts on to head, not to block. what block you use is un-important
swapstar is offline   Reply With Quote
Old 02-07-2006, 05:59 PM   #10
Matt Monson
Scooby Guru
 
Member#: 832
Join Date: Jan 2000
Chapter/Region: RMIC
Location: Teh Ghetto Garage, CO
Vehicle:
99 2.5RS, '85 911
'73 914 and 2012 BRZ

Default

nevermind...

Last edited by Matt Monson; 02-07-2006 at 06:07 PM.
Matt Monson is offline   Reply With Quote
Old 02-07-2006, 05:59 PM   #11
Zephyr
Scooby Specialist
 
Member#: 3362
Join Date: Dec 2000
Location: Central NJ
Vehicle:
2001 I've wired a
Few cars in my day

Default

you will have better luck, more reliablity and spend less money if you go with a WRX engine.

Those heads will fit that block. Some say they have a much better flow as well.
Zephyr is offline   Reply With Quote
Old 02-08-2006, 01:11 AM   #12
civic2scooby
Scooby Specialist
 
Member#: 78658
Join Date: Jan 2005
Chapter/Region: MWSOC
Location: East Lansing Michign
Vehicle:
2005 LGT Limited
Black/Black

Default

Quote:
Originally Posted by swapstar
how do you know? have you tried this or are you blurting out HEARSAY.

they bolt up just fine. all dual port heads have same pattern. you can swap a 1993 ej18 header on a 2005 sti ej257 pair of heads. thats no problem
sorry oh subaru master...when I was asking about an RS-T setup I was told by several members on here that the exhaust mani. from the WRX wouldnt bolt up to the SOHC heads.
civic2scooby is offline   Reply With Quote
Old 02-08-2006, 07:12 AM   #13
swapstar
*** Banned ***
 
Member#: 102779
Join Date: Dec 2005
Location: JDM land filling a container
Vehicle:
1998 PM if u need
JDM bits.....

Default

did they say this from experiance or from hearing somthing from their nextdoor neighbors cousins uncle? lotsa good info on these boards, if you have seen a picture or done it yourself, then it is probably true. otherwise......
swapstar is offline   Reply With Quote
Old 02-08-2006, 12:07 PM   #14
Matt Monson
Scooby Guru
 
Member#: 832
Join Date: Jan 2000
Chapter/Region: RMIC
Location: Teh Ghetto Garage, CO
Vehicle:
99 2.5RS, '85 911
'73 914 and 2012 BRZ

Default

Quote:
Originally Posted by swapstar
did they say this from experiance or from hearing somthing from their nextdoor neighbors cousins uncle? lotsa good info on these boards, if you have seen a picture or done it yourself, then it is probably true. otherwise......
oh, come on my friend. Just eat your hat and admit for once you didn't know the answer...
Matt Monson is offline   Reply With Quote
Old 02-08-2006, 12:10 PM   #15
Kawikid20o2
Scooby Specialist
 
Member#: 86291
Join Date: May 2005
Chapter/Region: NESIC
Location: New Fairfield, CT
Vehicle:
'97 LegaSTi-2.5XTR
'96 BrightonCoupeWRX-SR30

Default

I had a wrx header on my 2.2L n/a sohc motor, that worked. The EJ series motors should all be able to bolt to any EJ designed Ex.manifold as long as they are dual Ex.port heads. But then again the story could be different with the 2.5 SOHC.

The problem lies with the n/a X-member as well as the n/a water pump inlet hitting the cross pipe. If you are going to use a turbo exhaust manifold, it will set you up for the factory up pipe location.

There exists a custom made up pipe solution for turboing an n/a motor and not interfering with the Xmember, was it north ursalia that had it? maybe unique motorsports?

It uses the n/a ex.manifold, now it may not be the most efficient set up, as the ex. gases have to travel further before they reach the turbo, but it will work and you wont have to swap the xmember.

Hope this helps,

~Justin
Kawikid20o2 is offline   Reply With Quote
Old 02-08-2006, 01:07 PM   #16
Matt Monson
Scooby Guru
 
Member#: 832
Join Date: Jan 2000
Chapter/Region: RMIC
Location: Teh Ghetto Garage, CO
Vehicle:
99 2.5RS, '85 911
'73 914 and 2012 BRZ

Default

The problem with the uppipe is absolutely specific to the SOHC EJ25 heads. DOHC EJ25 and SOHC EJ22 heads have no problemo. There is some local guy here in Colorado who made the SOHC EJ25 heads work, but he had cut a big ole chunk out of the back or the head. Everyone who looked at them, myself included, thought he was nuts and should have just gotten a custom uppipe made up...

and Chad=Unique Motorsports= custom up-pipe...
Matt Monson is offline   Reply With Quote
Old 02-08-2006, 04:37 PM   #17
swapstar
*** Banned ***
 
Member#: 102779
Join Date: Dec 2005
Location: JDM land filling a container
Vehicle:
1998 PM if u need
JDM bits.....

Default

word. post a picture. id love to see hacked head.

skare. run away.
swapstar is offline   Reply With Quote
Old 02-08-2006, 05:13 PM   #18
Matt Monson
Scooby Guru
 
Member#: 832
Join Date: Jan 2000
Chapter/Region: RMIC
Location: Teh Ghetto Garage, CO
Vehicle:
99 2.5RS, '85 911
'73 914 and 2012 BRZ

Default

I know he used to post here, but don't remember his screenname. Saw the car at a local meet about 2 years ago and haven't seen it since...
Matt Monson is offline   Reply With Quote
Old 02-08-2006, 08:23 PM   #19
Kawikid20o2
Scooby Specialist
 
Member#: 86291
Join Date: May 2005
Chapter/Region: NESIC
Location: New Fairfield, CT
Vehicle:
'97 LegaSTi-2.5XTR
'96 BrightonCoupeWRX-SR30

Default

Chopped head sounds really interesting, Matt.... however I'm not smart enough to figure that one out.
Kawikid20o2 is offline   Reply With Quote
Old 02-08-2006, 10:27 PM   #20
swapstar
*** Banned ***
 
Member#: 102779
Join Date: Dec 2005
Location: JDM land filling a container
Vehicle:
1998 PM if u need
JDM bits.....

Default

the quesiton was bolt to head. not up pipe clearance. i stand uncorrected and correct.

haha
swapstar is offline   Reply With Quote
Old 02-09-2006, 02:54 AM   #21
civic2scooby
Scooby Specialist
 
Member#: 78658
Join Date: Jan 2005
Chapter/Region: MWSOC
Location: East Lansing Michign
Vehicle:
2005 LGT Limited
Black/Black

Default

Quote:
Originally Posted by swapstar
the quesiton was bolt to head. not up pipe clearance. i stand uncorrected and correct.

haha
that sound like some **** I would say
civic2scooby 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
NA EJ25 heads on EJ20? bigolrig Newbies & FAQs 6 10-01-2009 08:57 PM
WTB 2.5 NA longblock or just heads morrocco88 NWIC Private Classifieds 13 10-08-2007 10:42 AM
2.5 na block with wrx head gusty_1987 Subaru Conversions 0 12-21-2006 05:12 PM
WRX Valve Springs/Retainers on NA 2.5 DOHC Heads? MY99 2.5GT Normally Aspirated Powertrain 2 02-06-2006 01:01 PM
2.5 liter heads on 2.2 liter block evo2rex Subaru Conversions 1 01-27-2004 03:46 PM

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


Powered by vBulletin® Version 3.7.0
Copyright ©2000 - 2016, Jelsoft Enterprises Ltd.
Powered by Searchlight © 2016 Axivo Inc.
Copyright ©1999 - 2016, North American Subaru Impreza Owners Club, Inc.