Welcome to the North American Subaru Impreza Owners Club Thursday March 28, 2024
Home Forums Images WikiNASIOC Products Store Modifications Upgrade Garage
NASIOC
Go Back   NASIOC > NASIOC General > Motorsports > Autocross

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 05-06-2010, 12:46 PM   #1
xcdhridr
Scooby Specialist
 
Member#: 58865
Join Date: Apr 2004
Chapter/Region: RMIC
Location: CO
Vehicle:
2004 WRX
99ESP - Drew =)

Default Rear diffs... Subaru Viscous versus Subaru Clutch type

I had thought the rear diff on the 04 wrx was open so I was looking for a new rear diff for better auto-x ability. I guess long story short it's viscous. There's a chance I could swap in a old (89ish) xtr clutch type rear lsd in my car. Would it be worth it? What would be the advantages or would there be any?
* Registered users of the site do not see these ads.
xcdhridr is offline   Reply With Quote
Sponsored Links
* Registered users of the site do not see these ads.
Old 05-07-2010, 05:52 AM   #2
speedyHAM
Scooby Specialist
 
Member#: 48377
Join Date: Nov 2003
Chapter/Region: MWSOC
Location: "They eat fish soaked in lye"
Vehicle:
1996 Gutted, built
XP class Impreza L

Default

Yes you could swap one in if you change the ring and pinion. If it was in good shape the advantage is that you wouldn't spin a rear wheel while it was in the air as much as you do now. That said- finding one in good shape will probably be a challenge. I think you'd be better off getting a new clutch diff and having it installed in your current housing.

A clutch rear is the way to go in a Subaru. Between the tendency to dog leg through corners and the weak viscous LSD that comes stock the acceleration difference coming out of corners and the added ability to get the car to rotate under throttle with a clutch rear is worth it.
speedyHAM is offline   Reply With Quote
Old 05-07-2010, 07:53 AM   #3
neilschelly
Scooby Specialist
 
Member#: 94902
Join Date: Aug 2005
Chapter/Region: NESIC
Location: Merrimack, NH
Vehicle:
1989 Porsche 944S2
Beige

Default

Seconded. The viscous, especially if aged, is essentially an open diff. The clutch diffs are great. When I bought one from a late eighties Subaru XT a year or two back, it looked great inside too, but they are hard to come by at all these days because the Datsun guys love them too. YMMV, but it's worth it if you can find one.
-N
neilschelly is offline   Reply With Quote
Old 05-10-2010, 11:38 AM   #4
xcdhridr
Scooby Specialist
 
Member#: 58865
Join Date: Apr 2004
Chapter/Region: RMIC
Location: CO
Vehicle:
2004 WRX
99ESP - Drew =)

Default

I can't really say my current viscous is aged... but it does have some races on it and 60k miles. The clutch type that's available to me is old... and who know's how many miles. I haven't opened it yet. Are there syncros and or discs in there I should look for signs of wear?

Would the clutch type just have faster engagement for the rear so I can stop tripoding?

I'm bad with mechanics so I guess I don't really understand them yet.

I would have to swap my rear axles to run it so it's kind of a pain.
xcdhridr is offline   Reply With Quote
Old 05-11-2010, 03:43 PM   #5
neilschelly
Scooby Specialist
 
Member#: 94902
Join Date: Aug 2005
Chapter/Region: NESIC
Location: Merrimack, NH
Vehicle:
1989 Porsche 944S2
Beige

Default

A clutch type would engage, whereas the viscous would delay engagement and then not really engage too strongly. The clutch discs themselves could be visually inspected for wear. They need friction. They can be resurfaced/replaced if necessary.
-N
neilschelly is offline   Reply With Quote
Old 05-12-2010, 11:08 AM   #6
Storm
Scooby Guru
 
Member#: 5218
Join Date: Mar 2001
Chapter/Region: MWSOC
Location: SAUL'S Motorsports
Vehicle:
96L Most Over-
Developed Beater

Default

When shimmed for a little more preload, the clutch diff locks up very quickly. Just enough give to keep from breaking axles in grid/paddock and pushing out the backdoor of each corner entry, and strong enough to increase your midcorner speed by 3-5mph (be it on 4, 3 or 2 wheels).

Replacement clutches and belleville springs are still available, but a quick treatment with a media blaster will freshen up anything worn.....very-very effective and cheaper than new guts.

Jay
Quote:
Originally Posted by xcdhridr View Post
I can't really say my current viscous is aged... but it does have some races on it and 60k miles. The clutch type that's available to me is old... and who know's how many miles. I haven't opened it yet. Are there syncros and or discs in there I should look for signs of wear?

Would the clutch type just have faster engagement for the rear so I can stop tripoding?

I'm bad with mechanics so I guess I don't really understand them yet.

I would have to swap my rear axles to run it so it's kind of a pain.
Storm is offline   Reply With Quote
Old 05-13-2012, 11:38 PM   #7
SubaruImpreza_power
Scooby Guru
 
Member#: 13910
Join Date: Jan 2002
Chapter/Region: NESIC
Location: Greenwich, CT
Vehicle:
2005 Legacy GT
blue

Default

Which models came with a stock rear clutch type?
SubaruImpreza_power is offline   Reply With Quote
Old 05-14-2012, 12:20 AM   #8
eg33GC
Scooby Specialist
 
Member#: 206851
Join Date: Mar 2009
Chapter/Region: MWSOC
Vehicle:
56 Belair
Pro Street

Default

V1/2, some 3/4, and newer STi.
eg33GC is offline   Reply With Quote
Old 05-14-2012, 12:28 AM   #9
SubaruImpreza_power
Scooby Guru
 
Member#: 13910
Join Date: Jan 2002
Chapter/Region: NESIC
Location: Greenwich, CT
Vehicle:
2005 Legacy GT
blue

Default

yeah but some from the late 80's and early 90's had them too right? From what I understand it's hard to find the parts to rebuild it anyways?
SubaruImpreza_power is offline   Reply With Quote
Old 05-14-2012, 12:48 AM   #10
raynman
Scooby Newbie
 
Member#: 320016
Join Date: May 2012
Default

Clutch are best, but you need to remember that you need matching driveshafts as well.

Later models like yours will most likely be plug in (part of the driveshaft splines push into the diff), while earlier will be plug out.
raynman is offline   Reply With Quote
Old 05-14-2012, 10:25 AM   #11
SubaruImpreza_power
Scooby Guru
 
Member#: 13910
Join Date: Jan 2002
Chapter/Region: NESIC
Location: Greenwich, CT
Vehicle:
2005 Legacy GT
blue

Default

Yeah my driveshafts are plug in.. However without any source for a rebuild it seems pointless.
SubaruImpreza_power 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
R160 Subaru Datsun Clutch type LSD with 4.44 gears Diff pooparu2 NWIC Private Classifieds 1 05-03-2010 03:43 PM
Fs: 06-07 Rear Brakes, Rear Diff, Axles, Driveshaft, Springs+shocks, Clutch +flywheel mystilexzero Suspension/Brakes/Handling 31 07-03-2008 04:38 PM
WTB: 06 WRX pull-type clutch, pressure plate, fork, master cylinder, 3.7 FD rear diff gling NESIC Private Classifieds 0 06-07-2007 06:45 PM
WTB: 06 WRX pull-type clutch, pressure plate, fork, master cylinder, 3.7 FD rear diff gling Private 'Wanted' Classifieds 0 06-07-2007 05:54 PM
Interesting article on Subaru Viscous Diffs rao Factory 2.0L Turbo Powertrain (EJ Series Factory 2.0L Turbo) 2 04-23-2001 08:38 AM

All times are GMT -4. The time now is 06:07 AM.


Powered by vBulletin® Version 3.7.0
Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.
Powered by Searchlight © 2024 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.