Welcome to the North American Subaru Impreza Owners Club Monday February 10, 2025
Home Forums Images WikiNASIOC Products Store Modifications Upgrade Garage
NASIOC
Go Back   NASIOC > NASIOC Technical > Normally Aspirated 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 01-18-2005, 12:23 PM   #101
staticfritz
Scooby Specialist
 
Member#: 66934
Join Date: Jul 2004
Chapter/Region: NWIC
Location: Seattle WA
Vehicle:
2004 JBP FXT
2002 cammed OBS - RIP

Default

hey kyle...

this sounds pretty interesting. I'm running a phase 2 ej25 in my obs, with EL header scoming soon. I want to get a set of deltas in late febuary, and i'f i'm pulling things apart, upping the CR with heads too would be pretty cool. My questions lie along kyles (maybe we'll do them together?).

SUBSCRIBE
* Registered users of the site do not see these ads.
staticfritz is offline   Reply With Quote
Sponsored Links
* Registered users of the site do not see these ads.
Old 01-18-2005, 01:05 PM   #102
reddevil
Scooby Guru
 
Member#: 64673
Join Date: Jun 2004
Chapter/Region: NWIC
Location: portland
Vehicle:
1990 Legacy wagon
goes 12.387 @ 116.5

Default

Matt, I did say "old" and "years of use".........But how about "10 years or older!"
reddevil is offline   Reply With Quote
Old 01-18-2005, 02:55 PM   #103
quantum
Scooby Newbie
 
Member#: 73416
Join Date: Oct 2004
Location: PA
Vehicle:
05 CTS-v
Stealth Grey

Default

Anyone ever tried a partial block fill on a ej25, I'm theorizing that it would take care of a lot of strength problems with the block. I've heard one of the biggest causes for problems with this block is the cylendar walls can actually move or shift causing the head to blow (let me know if I was informed wrong). So I thought that a partial fill should add a lot of strength and still allow for enough cooling for high compression,nitrous, or turbo build ups. Any thoughts?
quantum is offline   Reply With Quote
Old 01-18-2005, 03:04 PM   #104
Storm
Scooby Guru
 
Member#: 5218
Join Date: Mar 2001
Chapter/Region: MWSOC
Location: SAUL'S Motorsports
Vehicle:
96L Most Over-
Developed Beater

Default

Uh....since it fills up the coolant passages....it's probably not a good idea for a streetcar.
Quote:
Originally Posted by quantum
Anyone ever tried a partial block fill on a ej25, I'm theorizing that it would take care of a lot of strength problems with the block. I've heard one of the biggest causes for problems with this block is the cylendar walls can actually move or shift causing the head to blow (let me know if I was informed wrong). So I thought that a partial fill should add a lot of strength and still allow for enough cooling for high compression,nitrous, or turbo build ups. Any thoughts?
Jay Storm
Storm is offline   Reply With Quote
Old 01-18-2005, 03:09 PM   #105
quantum
Scooby Newbie
 
Member#: 73416
Join Date: Oct 2004
Location: PA
Vehicle:
05 CTS-v
Stealth Grey

Default

That is why I was thinking a partial fill, Like a quarter the way up. I know tons of lt1 guys who have done a partial fill and a high volume water pump with a nice radiator and actually ran cooler.
quantum is offline   Reply With Quote
Old 01-18-2005, 03:58 PM   #106
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

There's not a whole lot of prep required to make one of these EJ22/EJ25 hybrids. The phase I vs phase II EJ22 heads thing has been argued for years around here. We used the phase I because that is what we had. They were the NA heads. The Turbo ones actually have a slightly smaller exhaust valve size and won't flow as well. But the phase I heads are dual port and let you bolt up Cobb, TWE or the other high end headers. For the single port phase II head, you could only use the Borla single port version.

We did nothing to the bottom end. Use a phase II if you can get it. Use the new four layer OEM EJ25 head gasket. With the phase I EJ22 heads, you are in the 11.5:1 CR range with this set up. We use 91 octane here because it is as high as we can get. All the sensors on the bottom end plug right in to the harness. You use your stock manifold and manifold wiring harness.

We did nothing with the ECU. One of the points of this swap is hp per $$$. It is a ghetto garage build. If you are gonna spend the money on EM, then spend the money on a built EJ25. We are using a torque chip. It helps down low. We bailed on the chipped ECU becuase it didn't like the torque chip. You could use an AFC if you wanted to play a little bit. But that's $200 more invested.

Gas mileage is in the low 20's. If you don't drive like you stole it, probably mid 20's would happen daily. I think that about covers it, for now...
Matt Monson is offline   Reply With Quote
Old 01-18-2005, 05:15 PM   #107
G.Subramaniam
Scooby Newbie
 
Member#: 64528
Join Date: Jun 2004
Default

Matt, anyone used wet nitrous on these 11:1 hybrids ?
G.Subramaniam is offline   Reply With Quote
Old 01-18-2005, 05:48 PM   #108
CirrusWRX
Scooby Guru
 
Member#: 17439
Join Date: Apr 2002
Chapter/Region: Tri-State
Location: Yardley, PA
Vehicle:
2010 WRX STI SE
Gray

Default

Quote:
Originally Posted by Matt Monson
There's not a whole lot of prep required to make one of these EJ22/EJ25 hybrids. The phase I vs phase II EJ22 heads thing has been argued for years around here. We used the phase I because that is what we had. They were the NA heads. The Turbo ones actually have a slightly smaller exhaust valve size and won't flow as well. But the phase I heads are dual port and let you bolt up Cobb, TWE or the other high end headers. For the single port phase II head, you could only use the Borla single port version.

We did nothing to the bottom end. Use a phase II if you can get it. Use the new four layer OEM EJ25 head gasket. With the phase I EJ22 heads, you are in the 11.5:1 CR range with this set up. We use 91 octane here because it is as high as we can get. All the sensors on the bottom end plug right in to the harness. You use your stock manifold and manifold wiring harness.

We did nothing with the ECU. One of the points of this swap is hp per $$$. It is a ghetto garage build. If you are gonna spend the money on EM, then spend the money on a built EJ25. We are using a torque chip. It helps down low. We bailed on the chipped ECU becuase it didn't like the torque chip. You could use an AFC if you wanted to play a little bit. But that's $200 more invested.

Gas mileage is in the low 20's. If you don't drive like you stole it, probably mid 20's would happen daily. I think that about covers it, for now...
Thank you kind sir!

Well, with the answers that Matt provided here and in other threads, and in combination what I've been piecing together, I, too, am looking to "build up" this ghetto frankenstein and try to keep it as low buck as possible. I figure I might try and get the delta cams at the same time since the engine will be out anyway, but otherwise, basically just apples to apples with a different block as far as it looks.

THANKS A TON!
CirrusWRX is offline   Reply With Quote
Old 01-18-2005, 07:10 PM   #109
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 G.Subramaniam
Matt, anyone used wet nitrous on these 11:1 hybrids ?
Just do it! You engage in far to much mental masturbation. Speed is better than sex. Get fast now!!!
Matt Monson is offline   Reply With Quote
Old 01-20-2005, 03:32 AM   #110
Crash477
Scooby Guru
 
Member#: 49881
Join Date: Dec 2003
Chapter/Region: South East
Location: Knoxville, TN
Vehicle:
2006 Subaru STi
1989 BMW 325is

Default

subscribe
Crash477 is offline   Reply With Quote
Old 01-20-2005, 10:57 AM   #111
huck369
Scooby Newbie
 
Member#: 26201
Join Date: Oct 2002
Chapter/Region: South East
Location: Somerset, KY
Vehicle:
2015 Impreza Premium
Charcoal

Subaru Stars

I'll most likely be doing this too.
for my MY00 RS, as it broke a timing belt, and since I'll have the heads off...and have a set of EJ22 NA stage I heads laying around, I'll throw them on it, hopefully it'll be a nice up in HP.

Huck
huck369 is offline   Reply With Quote
Old 01-20-2005, 11:37 AM   #112
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 huck369
I'll most likely be doing this too.
for my MY00 RS, as it broke a timing belt, and since I'll have the heads off...and have a set of EJ22 NA stage I heads laying around, I'll throw them on it, hopefully it'll be a nice up in HP.

Huck

Ah, this changes my opinion. Why would you use the EJ22 heads if your EJ25 heads are good? Use a thin .027 hg like I did and bump the CR on your EJ25. The EJ22 heads are a down grade. But if your EJ25 heads have bent valves, then it would be a good cheap option. Get the Delta cams while they are out. But remember, you are going to need an EJ22E manifold to make this bolt up.

If you need a manifold, pm me. I will sell you one for cheap. And if your heads are borked, I may be interested in picking them up for rebuilding if you will let them go cheap.

Lastly,
We are doing to R&D this weekend and plugging in the EJ22 ECU to the car. We want to see what differences we notice between the two. We will also have it on the dyno next month and will likely run it with both the 1.8 ECU and the 2.2...
Matt Monson is offline   Reply With Quote
Old 01-20-2005, 12:23 PM   #113
huck369
Scooby Newbie
 
Member#: 26201
Join Date: Oct 2002
Chapter/Region: South East
Location: Somerset, KY
Vehicle:
2015 Impreza Premium
Charcoal

Default

I haven't torn into it yet, but assume the valves are bent.
I just bought the car (wrecked) and the rad is pushed into the t-belt.
If I'm really lucky (which I usually am not) maybe a new t-belt will be all it needs, but I'd put money on some bent valves, and I'm looking ahead for my options.

And as I have a whole 92 MY EJ22 with a bottom end knock sitting in my garage, I can rob it to fix the 2.5, or at least it sounds like I can from what I've read in this thread.

It's my 20th Subaru, but have been mostly earlier EJ22's EJ18's and EG33's, EJ27's which are all non-interferance motors, so this will be something new for me.

But I have hope now anyways,
Thanks,
Huck
The originator of the SVX 5-speed swap
huck369 is offline   Reply With Quote
Old 01-20-2005, 12:55 PM   #114
huck369
Scooby Newbie
 
Member#: 26201
Join Date: Oct 2002
Chapter/Region: South East
Location: Somerset, KY
Vehicle:
2015 Impreza Premium
Charcoal

Default

Another quick question....
will I be able to run the 2.5 cams, and roller rockers in the EJ22 heads?

Huck
huck369 is offline   Reply With Quote
Old 01-20-2005, 01:21 PM   #115
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 huck369
Another quick question....
will I be able to run the 2.5 cams, and roller rockers in the EJ22 heads?

Huck
Nope. Totally different head design. Plus stock EJ25 cams aren't any more agressive than EJ22 cams anyways...
Matt Monson is offline   Reply With Quote
Old 01-21-2005, 10:26 AM   #116
CirrusWRX
Scooby Guru
 
Member#: 17439
Join Date: Apr 2002
Chapter/Region: Tri-State
Location: Yardley, PA
Vehicle:
2010 WRX STI SE
Gray

Default

EJ22E manifold - You're referring to intake manifold, correct? They are virtually the same all the way up through the 2.2L lifecycle from 94ish - 00+ are they not?
CirrusWRX is offline   Reply With Quote
Old 01-21-2005, 01:52 PM   #117
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 CirrusWRX
EJ22E manifold - You're referring to intake manifold, correct? They are virtually the same all the way up through the 2.2L lifecycle from 94ish - 00+ are they not?
read again. You cannot use an EJ22 manifold on Ej25 heads...
Matt Monson is offline   Reply With Quote
Old 01-21-2005, 02:47 PM   #118
huck369
Scooby Newbie
 
Member#: 26201
Join Date: Oct 2002
Chapter/Region: South East
Location: Somerset, KY
Vehicle:
2015 Impreza Premium
Charcoal

Default

Quote:
Originally Posted by Matt Monson
read again. You cannot use an EJ22 manifold on Ej25 heads...
But will have to to use a EJ22 intake manifold, when using the EJ22 heads on a EJ25....right?
huck369 is offline   Reply With Quote
Old 01-21-2005, 04:23 PM   #119
CirrusWRX
Scooby Guru
 
Member#: 17439
Join Date: Apr 2002
Chapter/Region: Tri-State
Location: Yardley, PA
Vehicle:
2010 WRX STI SE
Gray

Default

Quote:
Originally Posted by huck369
But will have to to use a EJ22 intake manifold, when using the EJ22 heads on a EJ25....right?
Yes -

Matt, I think you might have a type-o which is causing confusion (or I'm just an idiot when it comes to the naming of the manifolds...)

You write:

Quote:
Ah, this changes my opinion. Why would you use the EJ22 heads if your EJ25 heads are good? Use a thin .027 hg like I did and bump the CR on your EJ25. The EJ22 heads are a down grade. But if your EJ25 heads have bent valves, then it would be a good cheap option. Get the Delta cams while they are out. But remember, you are going to need an EJ22E manifold to make this bolt up.
That sentence is what screwed me up - do you mean EJ25E manifold? (all references that I am aware of regarding EJ22E is the 2.2L SOHC, am I wrong here?)
-----------------------------------

FINAL
EDIT: OK OK OK - I see what you were saying. You were saying to the guy if his valves are bent and his heads are toast and he DECIDED to go with the EJ22 heads (which you recommended against if his EJ25 heads are still good, which makes sense) then he would need the corresponding EJ22 manifold.

So class, in conclusion, the intake manifold needs to mate to your heads. EJ25 heads = EJ25 intake manifold

EJ22 heads = EJ22 intake manifold

REGARDLESS of what block you go with.
PHEW! Sorry for the momentary retardedness


-Cirrus "Master of the Obvious and Poor Reading Comprehension"
CirrusWRX is offline   Reply With Quote
Old 01-21-2005, 06:37 PM   #120
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

you got it.

-matt "master of the run-on thought"...
Matt Monson is offline   Reply With Quote
Old 01-31-2005, 10:18 PM   #121
G.Subramaniam
Scooby Newbie
 
Member#: 64528
Join Date: Jun 2004
Default

Bump--
G.Subramaniam is offline   Reply With Quote
Old 01-31-2005, 11:27 PM   #122
Kevin Thomas
Street Racing Instructor
Moderator
 
Member#: 110
Join Date: Jul 1999
Location: 1997 OBS, 1996 SVX, 1988 RX
Vehicle:
1989 1989 XT6

Default

Quote:
Originally Posted by Matt Monson
We did nothing to the bottom end. Use a phase II if you can get it. Use the new four layer OEM EJ25 head gasket. With the phase I EJ22 heads, you are in the 11.5:1 CR range with this set up. We use 91 octane here because it is as high as we can get. All the sensors on the bottom end plug right in to the harness. You use your stock manifold and manifold wiring harness.

Hey Matt! What is the part# for the headgasket you are referring to that is in bold above? Installing this gasket on my single (Siamesed) exhaust port 2.2ltr Outback Sport will yield an 11.5:1 compression ratio eh? Man.....got my head spinning.

So I can simply purchase this headgasket, take it to the dealership and they could install it without issue as if it was the stock headgasket? Interesting!
Kevin Thomas is offline   Reply With Quote
Old 02-01-2005, 08:20 AM   #123
huck369
Scooby Newbie
 
Member#: 26201
Join Date: Oct 2002
Chapter/Region: South East
Location: Somerset, KY
Vehicle:
2015 Impreza Premium
Charcoal

Default

Kevin,
The gaskets won't up your compression on your EJ22, it only ups the compression when you use EJ22 heads on the EJ25 block....its not the gaskets that bump it up...it's the heads, I think he's saying to use those gaskets as they hold up the best...

Huck
huck369 is offline   Reply With Quote
Old 02-02-2005, 09:21 AM   #124
Kevin Thomas
Street Racing Instructor
Moderator
 
Member#: 110
Join Date: Jul 1999
Location: 1997 OBS, 1996 SVX, 1988 RX
Vehicle:
1989 1989 XT6

Default

Quote:
Originally Posted by huck369
Kevin,
The gaskets won't up your compression on your EJ22, it only ups the compression when you use EJ22 heads on the EJ25 block....its not the gaskets that bump it up...it's the heads, I think he's saying to use those gaskets as they hold up the best...

Huck
Thank you Huck! I read kinda fast at work and sometimes do not get the whole 'gist' of the thread and/or posts. I'm relieved I won't be spending any money on this now. If it were just gaskets that would need changing, I'd pretty much be in trouble.
Kevin Thomas is offline   Reply With Quote
Old 02-04-2005, 08:02 PM   #125
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

yeah Kevin,
Hukc hit the nail on the head. Now, Cometic might make a thinner than stock HG that would let you do something like what I have done on my 2.5RS. It might be worth pursuing for some cheap power.
And don't pay the dealership for that job. It is a weekend job that just requires a certain amount of attention to detail. But it is not hard...
Matt Monson 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
Low Compression/High Boost vs High Compression/Low Boost? JoeTX Newbies & FAQs 35 12-13-2016 04:50 PM
What to do? High Compression, Low Boost or Low Compression, High Boost. FlooredSubaru Normally Aspirated with bolt-on Forced Induction Powertrain 6 01-29-2003 11:55 AM
Tuning hp and torque curve w/ low compression and high compression pistons FuJi K Normally Aspirated with bolt-on Forced Induction Powertrain 22 10-14-2001 08:25 PM
High Compression Jgrahn555 SVX Forum Archive 7 04-16-2001 01:31 AM
High compression pistons for NA? bsquare Normally Aspirated Powertrain 7 04-07-2001 11:56 AM

All times are GMT -4. The time now is 07:26 PM.


Powered by vBulletin® Version 3.7.0
Copyright ©2000 - 2025, Jelsoft Enterprises Ltd.
Powered by Searchlight © 2025 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.