Welcome to the North American Subaru Impreza Owners Club Friday August 29, 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 12-20-2002, 05:28 PM   #1
YaZahX
Scooby Specialist
 
Member#: 11932
Join Date: Nov 2001
Chapter/Region: Tri-State
Location: NY
Vehicle:
1998 CW ITR
2006 NBP SI

Default what to do.. looking for a 2.5RS but is the DOHC THAT bad?

im looking to sell my wrx and pick up a 2.5RS, currently im talking to a few dealers. 2 of them have DOHC cars.. another has a 00 RS. what would you do? i hear alot about DOHC phase 1 have head gaskit issues... i do plan to turbo the engine(and hopfully build up an engine in my garage aswell, but not definate)

i think i read that the awd system on the 00 is better(rear LSD or somthin) and that the parts are stronger, but i do like the blue of the my98. (i can deal either way) but also it looks that the parts in general are harder to find for the RS(wrx killed it) and that the DOHC parts are even harder(not to mention the MAF issue that comes with the pre 99s). should i just go for the 00 and 01 RS?
* Registered users of the site do not see these ads.
YaZahX is offline   Reply With Quote
Old 12-21-2002, 12:58 AM   #2
Jademonkey
Scooby Specialist
 
Member#: 9213
Join Date: Aug 2001
Location: My grandma was 6' 6"
Vehicle:
2000 RS
Red

Default

Go with the 00 or 01 RS.
Jademonkey is offline   Reply With Quote
Old 12-21-2002, 01:50 AM   #3
rhdude
Scooby Guru
 
Member#: 6637
Join Date: May 2001
Chapter/Region: MAIC
Location: Manassas
Vehicle:
2009 Acura MDX Sport

Default

Buy the 98, swap in the newer headgaskets, and pull a rear diff off a 00 or 01, and you'll have my choice...

Basicly, it comes down to: Can you replace headgaskets yourself, or would you have to pay a shop $1k to do it? 98's can be found for dirt cheap, and head gaskets are $24-31 depending on which dealer you go to. the Headgaskets are'nt that hard to replace if you know what you are doing and have the tools...

btw, the '99 has a fragile MAF, the 98 has a Strong MAF.. 00+ has a MAP

~Brian
rhdude is offline   Reply With Quote
Old 12-21-2002, 09:17 AM   #4
Benero
Scooby Newbie
 
Member#: 27993
Join Date: Oct 2002
Location: Caguas, Puerto Rico
Vehicle:
2000 Impreza RS
Silverthorn Metallic

Thumbs up Looking for a 2.5RS......

I own a 2000 RS so,.....I would say, go for the MY00. Price on the few performance parts left is going down, so you can add some spice to a great performing car with less money. The only concers is with the transmision. You should treat it nice since they are a bit fragile. Have a few friends of mine who have blown the second gear due to hard shifting. Just remember this is not a drag race car. But hit the gas in a curvy road and you 'll feel the Beauty of All Wheel Drive. It will be hard, very hard to catch you. Any fool can go fast on a straight line, but it takes guts and knowledge to go fast on a curvy road.
Good driving
Benero is offline   Reply With Quote
Old 12-21-2002, 09:37 AM   #5
YaZahX
Scooby Specialist
 
Member#: 11932
Join Date: Nov 2001
Chapter/Region: Tri-State
Location: NY
Vehicle:
1998 CW ITR
2006 NBP SI

Default

so if i replace the headgaskits 1 time i wont have the over heating issue again? or does it happen over and over again...?

i also plan to try to turbo it..

the rear diff i would just have to swap?
YaZahX is offline   Reply With Quote
Old 12-21-2002, 09:44 AM   #6
Roo
Scooby Specialist
 
Member#: 14931
Join Date: Feb 2002
Chapter/Region: BAIC
Location: between redwoods and vineyards
Talking Head Gasket Issue

Quote:
Originally posted by YaZahX
so if i replace the headgaskits 1 time i wont have the over heating issue again? or does it happen over and over again...?

i also plan to try to turbo it..

the rear diff i would just have to swap?
I have a Phase I motor in a Forester (Same engine '98), and I had the head gaskets done in September. I have since taken it on back roads at speeds that would scare most people, and it hasn't overheated at all. Of course, put some Water Wetter in the coolant mix when you do, and if you do the job right, it should never overheat. (Even when driving 1xx, revving hard, running over WRX's, etc.)

-Roo

'It's not speeding if you don't get caught'
Roo is offline   Reply With Quote
Old 12-21-2002, 10:39 AM   #7
YaZahX
Scooby Specialist
 
Member#: 11932
Join Date: Nov 2001
Chapter/Region: Tri-State
Location: NY
Vehicle:
1998 CW ITR
2006 NBP SI

Default

but whats the problem on it? the block or the actual gaskits?

are there any other issues other than that?(i did look in the faq)
YaZahX is offline   Reply With Quote
Old 12-21-2002, 12:40 PM   #8
rhdude
Scooby Guru
 
Member#: 6637
Join Date: May 2001
Chapter/Region: MAIC
Location: Manassas
Vehicle:
2009 Acura MDX Sport

Default

Subaru used a really bad head gasket design on the '98s... Since then they have produced a new headgasket for the '98 that is very strong and I have'nt heard anyone having problems with the new gaskets. Just replace the old-style gaskets with the new-style gaskets and you should'nt have any worries.

If you are going turbo, just remember the '98 has a lower compression ratio (good thing)
rhdude is offline   Reply With Quote
Old 12-21-2002, 01:02 PM   #9
YaZahX
Scooby Specialist
 
Member#: 11932
Join Date: Nov 2001
Chapter/Region: Tri-State
Location: NY
Vehicle:
1998 CW ITR
2006 NBP SI

Default

Quote:
Originally posted by rhdude
Subaru used a really bad head gasket design on the '98s... Since then they have produced a new headgasket for the '98 that is very strong and I have'nt heard anyone having problems with the new gaskets. Just replace the old-style gaskets with the new-style gaskets and you should'nt have any worries.

If you are going turbo, just remember the '98 has a lower compression ratio (good thing)
thanks for your help aswell. i think im 75% sure that i wanna go with the 98, just 1 other question, will i be able to find enine parts for this particular engine if i need any?

(i do plan to build an engine, but i just wanna know for if somthing comes up)
YaZahX is offline   Reply With Quote
Old 12-21-2002, 02:08 PM   #10
rhdude
Scooby Guru
 
Member#: 6637
Join Date: May 2001
Chapter/Region: MAIC
Location: Manassas
Vehicle:
2009 Acura MDX Sport

Default

yes... The only things to remember are, you have to buy twice as many cams... and injectors are a bit harder to find, but you can use injectors from the ver5 STi, or the SR20DET motors, I've also heard you can use 300ZX injectors. Internals you should be able to find if you look, and I know Paeco sells internals for it. I myself and switching over to a EJ22g(turbo) motor because it has a stronger block, stock forged rods, and oil squiters. I'll mate up my EJ25D heads and I think it'll be a nice pair. I'll sacrifice the .3L of torque for safety and ability to run higher boost without having to mod the internals.

~Brian
rhdude is offline   Reply With Quote
Old 12-21-2002, 02:19 PM   #11
RebelINS
Scooby Specialist
 
Member#: 2953
Join Date: Nov 2000
Chapter/Region: MWSOC
Location: Rochester, MI, USA
Vehicle:
2000 Impreza 2.5RS
2005 Impreza WRX STi

Default

Cosmetically I would recommend doing a bumper swap from a 99-01 RS, they just look better.

-Wes
RebelINS is offline   Reply With Quote
Old 12-21-2002, 02:24 PM   #12
Tobias_Ostapchuk
Scooby Newbie
 
Member#: 554
Join Date: Nov 1999
Location: Darien, CT, USA
Vehicle:
2002 Subaru WRX S/W
Aspen White

Default

I rebuilt the motor at 36,000 miles in my 1998 DOHC 2.5RS, and then promptly sold the car for a WRX.

On motors, my friend has a 1998 Outback and he needs to rebuild his 2.5 this week. There is 74,000 miles on the car, and it has NEVER been abused.

Also, my 2.5 RS had a great appetite for rear wheel bearings.

Stick to a MY99 and onward SOHC car.

-Tobias
Tobias_Ostapchuk is offline   Reply With Quote
Old 12-21-2002, 02:25 PM   #13
YaZahX
Scooby Specialist
 
Member#: 11932
Join Date: Nov 2001
Chapter/Region: Tri-State
Location: NY
Vehicle:
1998 CW ITR
2006 NBP SI

Default

Quote:
Originally posted by RebelINS
Cosmetically I would recommend doing a bumper swap from a 99-01 RS, they just look better.

-Wes
dont worry, i will i just have a thing for liking dohc

what i wanna do is turbo this motor(using wrx pipes due to the dohc thing) and build up a 2.2 block, run 9:1 CR put a stroker crank to give me 2.5L of displacment and do all engine internals

Quote:
Also, my 2.5 RS had a great appetite for rear wheel bearings.
are 99 and up wheel bearings interchangeable?(the rear ends going to go anyway, maybe i should just pick up all the parts)
YaZahX is offline   Reply With Quote
Old 12-21-2002, 03:22 PM   #14
rhdude
Scooby Guru
 
Member#: 6637
Join Date: May 2001
Chapter/Region: MAIC
Location: Manassas
Vehicle:
2009 Acura MDX Sport

Default

I've never heard of anyone having to rebuild a MY98 block... I cracked my #4 cyl, but that was'nt cause of the block....

The wheels bearings in all 98-01 impreza's go bad... you can swap them out with Legacy bearings and you should'nt have problems.

the bumper swap is easy enough to do... I love mine..

You know this really pisses me off, all the people who don't know how to work on their car, or people who just "read somewhere that a 99+ is so much better and 98's are the devil" come in and try to give good info... I mean just go away unless you are really going to help YaZ out, since thats what he asked for....

If you are going to be building a motor, why even worry about the stock motor?
rhdude is offline   Reply With Quote
Old 12-21-2002, 08:34 PM   #15
jdk
Scooby Newbie
 
Member#: 26114
Join Date: Oct 2002
Location: Reno
Vehicle:
06 rs

Arrow

...good info?...ok, since he hasn't bought it yet...pound for pound, dollar for dollar, the '00,'01 is better to start w/ for various reasons lsd,map,engine internal structure,head gaskets(better daily driver overtime) . DONT get the '98 for the heads, much better option would be to put the wrx heads on(dohc)
jdk is offline   Reply With Quote
Old 12-22-2002, 01:35 PM   #16
joemamad
Scooby Newbie
 
Member#: 27269
Join Date: Oct 2002
Default 2.5RS DOHC head gaskets

HI this is Joe I've just finished rebuilding my 2.5 DOHC phase I motor. Bad head gaskets. This was my second motor in a 97 Outback Sw, with a 5SP tranny. I put in the new head gaskets and everything seems fine (3 weeks).. See my post in the Legacy forum for more details.
joemamad is offline   Reply With Quote
Old 12-22-2002, 02:12 PM   #17
rhdude
Scooby Guru
 
Member#: 6637
Join Date: May 2001
Chapter/Region: MAIC
Location: Manassas
Vehicle:
2009 Acura MDX Sport

Default

erg... not to sound mean or anything.... But replacing headgaskets is not the same thing as rebuilding a motor....
rhdude is offline   Reply With Quote
Old 12-22-2002, 09:35 PM   #18
lucien2
Scooby Specialist
 
Member#: 1519
Join Date: May 2000
Chapter/Region: MAIC
Location: Baltimore, hon!
Vehicle:
1998 Volvo V70R
Silver

Default

I'm about to roll 60k on my Phase I without a hitch (although it does have the newer block). Y'know, I read about all these criticisms of the 2.5, that it is slow, and that the DOHC isn't as good as the SOHC..... I don't know as much about mechanicals as Brian, but I do know that this engine is good for decent speed, makes its power in a more usable rpm range than the SOHC, and is generally a low budget hoot (especially with a little help from a cat-back). *shrug* Sure I'd like a turbo, but I never felt this car was a dog.
lucien2 is offline   Reply With Quote
Old 12-22-2002, 11:49 PM   #19
damianq
Scooby Specialist
 
Member#: 5380
Join Date: Apr 2001
Location: Edmonton
Vehicle:
1999 Impreza
Primer

Default

I'll address something that no one has touched on yet...
If you are thinking of adding a turbo, get the DOHC heads. They ARE based in the WRX heads the rest of the word got. The Phase 1 EJ25 does NOT produce as much torque as do the Phase 2, period, in NA. But if you want to add a turbo at somepoint, the DOHC heads are the better choice. It flows a higher CFCM than the SOHC. The DOHC design is also much more rev friendly, such that it can rev faster, longer. For some reason the SOHC just isn't good at revving considering it has much lower mass & less frictional drag... odd. The combustion chamber volume is also slightly larger than the SOHC - helps to prevent ping (although the SOHC chamber shape is better. Even w/ 4 cams the the DOHC engines are also easier to tune, IMHO. If you look around you can find mild WRX upgrade cams that can be used w/o any interference problems (look down under). For turbo, MAF if better/easier. Now all that is if you are going turbo. Overall, the MY00 & 01 cars are better in many other respects. This is all from personal exp. which has cost me tonnes.
damianq is offline   Reply With Quote
Old 12-23-2002, 08:44 AM   #20
Gambit
Scooby Specialist
 
Member#: 102
Join Date: Jul 1999
Location: The meeting place
Default

Well since u're choosing b/t a 98RS and a newer 2000/2001 RS, other than the engines and of course the rear LSD, have a look at the interior. The 98RS' looks like the regular Impreza L or the OBS interior whereas the later RS has a much improved interior. have a detail compare b/t the both car's interior.
Gambit is offline   Reply With Quote
Old 12-23-2002, 08:09 PM   #21
YaZahX
Scooby Specialist
 
Member#: 11932
Join Date: Nov 2001
Chapter/Region: Tri-State
Location: NY
Vehicle:
1998 CW ITR
2006 NBP SI

Default

Quote:
Originally posted by Gambit
Well since u're choosing b/t a 98RS and a newer 2000/2001 RS, other than the engines and of course the rear LSD, have a look at the interior. The 98RS' looks like the regular Impreza L or the OBS interior whereas the later RS has a much improved interior. have a detail compare b/t the both car's interior.
good point!

is the inside like this on the 98:
YaZahX is offline   Reply With Quote
Old 12-23-2002, 08:55 PM   #22
gxt120
Scooby Newbie
 
Member#: 3189
Join Date: Dec 2000
Location: Long Island, NY
Vehicle:
2001 Impreza 2.5RS
STM

Default

No, that is a pre 98 interior. The interior of the 98 RS differs from the 99-01 in that it has:

Black face gauges instead of white
Rubber shift boot instead of leather
Different color (I think lighter) fabric
No fake carbon fiber trim like on the 01'

I say just change the shift boot and you are set!
gxt120 is offline   Reply With Quote
Old 12-24-2002, 02:17 PM   #23
joemamad
Scooby Newbie
 
Member#: 27269
Join Date: Oct 2002
Default 2.5 ltr rebuild

Yo this is Joe

My gasket job included changing all top-end seals oil-pump work, valve adjustment etc. The oly thing I did not do was split the block and replace the crank bearings or bore cylinders Check out my earlier post for more info
joemamad is offline   Reply With Quote
Old 12-24-2002, 07:37 PM   #24
ilmaestro
Scooby Specialist
 
Member#: 16004
Join Date: Mar 2002
Location: Folsom, CA
Vehicle:
1998 2.5 RS - Blue
Dreaming of Boost

Default

When I bought my 98 car, it had 40k miles on it. I think it is safe to say that many 98 cars have already had the haed gasket replaced. With my car, this was the case. Overall, I am happy with my DOHC... the interior of my car is just as gxt120 mentioned, it, almost exactly the same as any other RS, except I have leather! The only thing that I would change is the bumper. You might want to consider that as a bumper swap will cost about 600 for parts and however much to get it painted.

good luck
jonathan
ilmaestro 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
Looking for a 2.5RS Coupe on the West Coast Virusx86 Private 'Wanted' Classifieds 0 01-08-2008 03:07 PM
Is the WRX that bad looking? aussie_rex General Community 88 10-23-2007 06:51 PM
Looking for a 2.5RS for sale locally Seth W North West Impreza Club Forum -- NWIC 6 06-10-2003 03:10 PM
Got $2k to spend what should I get for my 2.5rs? R2G2_54 Southern California Impreza Club Forum -- SCIC 24 09-25-2002 08:01 PM
Wheres the cheapest place to buy sideskirts for 00 2.5rs sedan AustinSTi Interior & Exterior Modification 8 10-31-2001 12:49 PM


All times are GMT -4. The time now is 10:12 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.