Welcome to the North American Subaru Impreza Owners Club Sunday July 13, 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 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 02-07-2013, 01:27 AM   #26
jamal
Scooby Guru
 
Member#: 71875
Join Date: Oct 2004
Location: Montana
Vehicle:
98 2.5GT
my wheels fit

Default

Quote:
Originally Posted by Bluefoton View Post
it'd be nice to clear that up once and for all. So 642s for EJ251 and 770 for EJ253? Is there any difference in between coolant passages on the head in these two N/A engines?
Phase 1 dohc is -610, which is a thicker MLS gasket
Phase 2 sohc to somewhere around 08-09 should use -642, which is the 04-06 turbo gasket. So that includes the 251 and 253 I think.
09 ish and up already have the -770 MLS gasket in them, which is the same thickness as 642 but has different cooling passages.

I think the change was whenever they started putting avcs or avls or whatever it is on the n/a 2.5s.
* Registered users of the site do not see these ads.
jamal is offline   Reply With Quote
Old 02-07-2013, 11:50 AM   #27
Sir-Knight
Scooby Specialist
 
Member#: 73636
Join Date: Nov 2004
Chapter/Region: E. Canada
Location: the 'wa, ontario, canada
Vehicle:
2007 Impreza 2.5i SE
newport blue pearl

Default

I believe that year would've been 05 in USDM, if not 06 for sure.
Sir-Knight is offline   Reply With Quote
Old 02-09-2013, 01:02 PM   #28
Bluefoton
Scooby Specialist
 
Member#: 141373
Join Date: Feb 2007
Chapter/Region: E. Canada
Location: Quebec, QC
Vehicle:
2008 2.5i-hatch -
now with a HID retrofit

Default

Aren't coolant passages supposed to match the holes in the head/block? If the head design didn't change in between 07-08-09, why would the HG differ?
Bluefoton is offline   Reply With Quote
Old 02-09-2013, 02:16 PM   #29
jamal
Scooby Guru
 
Member#: 71875
Join Date: Oct 2004
Location: Montana
Vehicle:
98 2.5GT
my wheels fit

Default

Yeah, the head design did change. If avcs was added in 05-06 I guess that's not when it was, but I remember seeing an 09 or '10 outback with the new -770 gaskets.

There's a picture of it here:

http://forums.nasioc.com/forums/show....php?t=2155089
jamal is offline   Reply With Quote
Old 02-12-2013, 10:30 PM   #30
cdwahl
Scooby Newbie
 
Member#: 144605
Join Date: Mar 2007
Chapter/Region: BAIC
Vehicle:
2007 2.5i Wagon
Satin White Pearl

Default

Quote:
Originally Posted by jamal View Post
Phase 1 dohc is -610, which is a thicker MLS gasket
Phase 2 sohc to somewhere around 08-09 should use -642, which is the 04-06 turbo gasket. So that includes the 251 and 253 I think.
09 ish and up already have the -770 MLS gasket in them, which is the same thickness as 642 but has different cooling passages.

I think the change was whenever they started putting avcs or avls or whatever it is on the n/a 2.5s.
What about for valve cover gaskets, will the dealer have MLS?

I need to replace my valve cover gaskets and I am not excited to install the same ones that failed after 60-90k...

Last edited by cdwahl; 02-12-2013 at 10:31 PM. Reason: typos...
cdwahl is offline   Reply With Quote
Old 02-13-2013, 12:36 AM   #31
rhino6303
Scooby Newbie
 
Member#: 181314
Join Date: May 2008
Chapter/Region: NWIC
Location: SW Washington
Vehicle:
2005 Impreza OBS SRR
05 Legacy GT RBP

Default

Quote:
Originally Posted by cdwahl View Post

What about for valve cover gaskets, will the dealer have MLS?

I need to replace my valve cover gaskets and I am not excited to install the same ones that failed after 60-90k...
The valve cover gaskets are not steel. So you can't get any mls valve cover gaskets. The oem ones work fine as long as you follow the fsm and also make sure all surfaces are clean when installing.
rhino6303 is offline   Reply With Quote
Old 02-13-2013, 10:35 PM   #32
cdwahl
Scooby Newbie
 
Member#: 144605
Join Date: Mar 2007
Chapter/Region: BAIC
Vehicle:
2007 2.5i Wagon
Satin White Pearl

Default

So you think that they failed because they weren't installed properly at the factory?
cdwahl is offline   Reply With Quote
Old 02-14-2013, 12:26 AM   #33
rhino6303
Scooby Newbie
 
Member#: 181314
Join Date: May 2008
Chapter/Region: NWIC
Location: SW Washington
Vehicle:
2005 Impreza OBS SRR
05 Legacy GT RBP

Default

They are a wear item. Getting 90k out of the valve cover gaskets is great.
rhino6303 is offline   Reply With Quote
Old 02-17-2013, 10:36 AM   #34
MikeC5
Scooby Newbie
 
Member#: 104702
Join Date: Jan 2006
Location: South Eastern CT
Vehicle:
95 Legacy
Green

Default

So has anyone used the 11044AA642 (MLS) gaskets on an 2.5 NA? Specifically, for a 2002 engine.
MikeC5 is offline   Reply With Quote
Old 02-17-2013, 11:32 AM   #35
rhino6303
Scooby Newbie
 
Member#: 181314
Join Date: May 2008
Chapter/Region: NWIC
Location: SW Washington
Vehicle:
2005 Impreza OBS SRR
05 Legacy GT RBP

Default

Yes. It has been done a lot on 2.5 n/a motors all the way up until they changed the coolant chamber designs.
rhino6303 is offline   Reply With Quote
Old 02-17-2013, 12:11 PM   #36
walhalla
Scooby Newbie
 
Member#: 333084
Join Date: Sep 2012
Default

how much is compression is effected
walhalla is offline   Reply With Quote
Old 02-17-2013, 12:43 PM   #37
Bluefoton
Scooby Specialist
 
Member#: 141373
Join Date: Feb 2007
Chapter/Region: E. Canada
Location: Quebec, QC
Vehicle:
2008 2.5i-hatch -
now with a HID retrofit

Default

0.1 increase in CR
Bluefoton 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


All times are GMT -4. The time now is 10:30 AM.


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.