Welcome to the North American Subaru Impreza Owners Club Wednesday October 22, 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 12-09-2002, 04:29 PM   #1
dpjef
Scooby Newbie
 
Member#: 18984
Join Date: May 2002
Location: Belgium
Vehicle:
2002 Impreza 2.0
dark blue

Question SOHC and DOHC

What's the advantage of having a DOHC against a SOHC ?

I myself drive an Impreza 2.0 N/A which is SOHC, the WRX is DOHC.

Thanx
* Registered users of the site do not see these ads.
dpjef is offline   Reply With Quote
Old 12-09-2002, 07:57 PM   #2
SJwrx
Scooby Specialist
 
Member#: 14970
Join Date: Feb 2002
Chapter/Region: BAIC
Location: San Jose, CA
Vehicle:
1997 GF8
multi

Default

SOHC (single over-head cam)
DOHC (dual '')

DOHC's usually produce more power due to you can adjust the cams functions easier and more prcisely.

Thats the jist (I think )

Rich
SJwrx is offline   Reply With Quote
Old 12-10-2002, 08:42 AM   #3
dpjef
Scooby Newbie
 
Member#: 18984
Join Date: May 2002
Location: Belgium
Vehicle:
2002 Impreza 2.0
dark blue

Default

I was just wondering because I read somewhere on the forum that Subaru went from DOHC to SOHC on the RS in 1997, I think.
dpjef is offline   Reply With Quote
Old 12-10-2002, 11:25 AM   #4
mrbell
Scooby Specialist
 
Member#: 1871
Join Date: Jul 2000
Location: Salt Lake City, UT
Vehicle:
2000 Impreza 2.5RS
Blue Ridge Pearl

Default

DOHC can have more tuning potential, due to ease of adjustment. You can adjust cam timing individually, affecting overlap. SOHC can be just as tuned, but it requires new cams. There's really no inherent advantage of DOHC, but it does sometimes make things easier. One subaru specific issue, though, is that the DOHC valves have a wider splay angle wrt each other and therefore a higher pent combustion chamber. This is probably more optimal for combustion, but may have other issues. Otherwise the SOHC would probably have the same angle.
mrbell is offline   Reply With Quote
Old 12-10-2002, 11:34 AM   #5
rhdude
Scooby Guru
 
Member#: 6637
Join Date: May 2001
Chapter/Region: MAIC
Location: Manassas
Vehicle:
2009 Acura MDX Sport

Default

the RS changed over in '99 with the phase 2 motor. A few '99s still had the phase 1 DOHC 4cam motor.
everything has pretty much been said, I'll add two things..
1. DOHC motors you have to pull the cams to remove the head, SOHC you don't have to...
2. DOHC cams are obviously more expensive. They are more of a pain to time as well.

~Brian
rhdude is offline   Reply With Quote
Old 12-10-2002, 12:20 PM   #6
dpjef
Scooby Newbie
 
Member#: 18984
Join Date: May 2002
Location: Belgium
Vehicle:
2002 Impreza 2.0
dark blue

Thumbs up

Thanks for the input, all.
dpjef 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
EJ20 SOHC and DOHC HEADS FOR SALE!!!!!! herbine2001 Engine/Power/Exhaust 6 04-26-2010 11:15 PM
sohc and dohc heads midnight2.5rs-t Subaru Conversions 3 01-19-2008 04:26 PM
difference between sohc and dohc oil pan? bryan_johnson Normally Aspirated Powertrain 2 02-16-2005 02:34 PM
EJ25 SOHC to DOHC and back again? JoShYo Normally Aspirated Powertrain 16 11-14-2003 11:24 AM
Technical differences b/w SOHC and DOHC engines 2.5GT Normally Aspirated Powertrain 1 12-07-2001 11:25 AM


All times are GMT -4. The time now is 10:15 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.