Welcome to the North American Subaru Impreza Owners Club Wednesday August 20, 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 08-15-2003, 02:26 AM   #1
AntonioS
Scooby Newbie
 
Member#: 23233
Join Date: Aug 2002
Location: Puerto Rico
Vehicle:
2000 2.5RS-T
white

Default compresion on a SOHC

what is the compresion of a SOHC 2.5l stock engine?????
* Registered users of the site do not see these ads.
AntonioS is offline   Reply With Quote
Old 08-15-2003, 02:42 AM   #2
Thead
Scooby Newbie
 
Member#: 16412
Join Date: Mar 2002
Location: Seattle, WA
Vehicle:
99 2.5RS
Slllooww Silver

Default

IIRC (but probably not)

99- 10:1
00-01- 11:1
Thead is offline   Reply With Quote
Old 08-15-2003, 03:27 AM   #3
Penphoe
Friendly Neighbourhood
Moderator
 
Member#: 269
Join Date: Sep 1999
Chapter/Region: VIC
Location: Burnaby, B.C., Canada
Vehicle:
2005 ABP LGT LTD BP6
00 Impreza RS GM6 RIP

Default

Quote:
Originally posted by Thead
IIRC (but probably not)

99- 10:1
00-01- 11:1
I believe the MY99's were 9.7 and the MY0x's are 10:1.

Whatever. They're around 10:1

LaterZ!
Darren!!
Penphoe is offline   Reply With Quote
Old 08-15-2003, 09:21 AM   #4
DanzBorin
Subaru Bounty Hunter
Moderator
 
Member#: 7131
Join Date: Jun 2001
Chapter/Region: TXIC
Location: Houston - Back in the Alief
Vehicle:
2008 STi DGM (3rd
STI) prev 05 STi (white)

Default

Quote:
Originally posted by Penphoe
I believe the MY99's were 9.7 and the MY0x's are 10:1.

Whatever. They're around 10:1

LaterZ!
Darren!!
we have a winnah!
DanzBorin is offline   Reply With Quote
Old 08-15-2003, 11:55 AM   #5
Compressed
Scooby Newbie
 
Member#: 12271
Join Date: Nov 2001
Location: Colorado
Vehicle:
2012 4Runner TE
KDSS!

Default

yup 10.0:1.

see here
Compressed is offline   Reply With Quote
Old 08-15-2003, 02:46 PM   #6
AntonioS
Scooby Newbie
 
Member#: 23233
Join Date: Aug 2002
Location: Puerto Rico
Vehicle:
2000 2.5RS-T
white

Default

OK But what compression should the gauge read on every cylinder??
AntonioS is offline   Reply With Quote
Old 08-15-2003, 04:26 PM   #7
Penphoe
Friendly Neighbourhood
Moderator
 
Member#: 269
Join Date: Sep 1999
Chapter/Region: VIC
Location: Burnaby, B.C., Canada
Vehicle:
2005 ABP LGT LTD BP6
00 Impreza RS GM6 RIP

Default

Quote:
Originally posted by AntonioS
OK But what compression should the gauge read on every cylinder??
Ah, that's a different thing. You'll have to look that up in a service manual. There'll be an acceptable range where the numbers can vary. I"m sure someone has posted that up somewhere.

Try searching for cylinder compression or something like that.

LaterZ!
Darren!!
Penphoe is offline   Reply With Quote
Old 08-15-2003, 04:54 PM   #8
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

Are you guys talking static or dynamic compression because they are two different numbers, and the winning response mixed them I do believe. No winner yet.
Matt Monson is offline   Reply With Quote
Old 08-15-2003, 05:15 PM   #9
DanzBorin
Subaru Bounty Hunter
Moderator
 
Member#: 7131
Join Date: Jun 2001
Chapter/Region: TXIC
Location: Houston - Back in the Alief
Vehicle:
2008 STi DGM (3rd
STI) prev 05 STi (white)

Default

Quote:
Originally posted by Matt Monson
Are you guys talking static or dynamic compression because they are two different numbers, and the winning response mixed them I do believe. No winner yet.
actually he's right... 99s have 9.7:1 and 00-01 have 10.0:1
DanzBorin is offline   Reply With Quote
Old 08-15-2003, 05:58 PM   #10
Eric SS
Sooby Guru
 
Member#: 1914
Join Date: Jul 2000
Chapter/Region: SWIC
Location: 2013 335i, 2011 G37 coupe
Vehicle:
2000 2.5RS w/ EJ22T
swap and N20. gone. : (

Default

Not sure about Subaru's calculations, but every time I do a compression calculator on a SOHC 2000-2001 EJ25 I get near 11.2:1

Not sure if some of Subaru's published data is wrong or if there is some other change they didn;t tell us about.
Eric SS is offline   Reply With Quote
Old 08-15-2003, 06:30 PM   #11
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

Actually,

1996 Phase I SOHC 9.5:1 rated at 155hp
'97-99 Phase I S&DOHC 9:71:1 rated at 165hp
'00-later Phase II 9.5:1 rated at 165 hp,
the 10.1:1 was the static compression which is higher. No idea why SOA changed which way they were reporting it, but they were inconsistent

What's my prize?
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
Need Suby Engine Guru Help On EJ25 SOHC Cam Question! NW OBS Normally Aspirated Powertrain 4 10-18-2006 12:28 AM
Oil fill tube to go on my sohc heads White 2.5rs Private 'Wanted' Classifieds 2 05-07-2006 02:01 PM
Trigger Pattern Group? on EJ25 SOHC Flying Subie Engine Management & Tuning 0 02-18-2006 10:12 PM
Flow numbers on my SOHC Ej25 heads Matt Monson Normally Aspirated Powertrain 33 11-18-2005 08:01 PM
Vavle Lash on 99 sohc heads? ASAP! chrismindless Normally Aspirated with bolt-on Forced Induction Powertrain 5 06-19-2005 08:56 AM


All times are GMT -4. The time now is 03:49 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.