The Subaru SVX World Network   SVX Network Forums
Live Chat!
SVX or Subaru Links
Old Lockers
Photo Post
How-To Documents
Message Archive
SVX Shop Search
IRC users:

Go Back   The Subaru SVX World Network > SVX Main Forums > General SVX Babble

Reply
 
Thread Tools Display Modes
  #16  
Old 07-16-2006, 11:45 PM
dynomatt dynomatt is offline
Registered User
 
Join Date: Apr 2006
Location: Canberra...Capital of Australia
Posts: 883
Registered SVX
JJ...of course, why didn't I think of you!!! Thanks

Mychailo, thanks to your link it turns out the US only differs in 5th and 6th and a company does the 5th and 6th JDM gears separately. Sooo...what about the US ones? I've widened my search on Nasioc and there's a few come up. Seems around $3k is about the going rate plus or minus?

Anybody got an inside running on the US ones either?

M
Reply With Quote
  #17  
Old 07-18-2006, 08:07 AM
mbtoloczko's Avatar
mbtoloczko mbtoloczko is offline
sans SVX
 
Join Date: Sep 2002
Location: Richland, WA
Posts: 4,250
Send a message via AIM to mbtoloczko
Matt, The US spec 6MTs all have the DCCD center diff. Without the OEM controller electronics and sensors installed, the diff operates as a rear biased open diff, i.e., no limited-slip action at all in the center diff. That's wouldn't be my first choice for an offroad rally car. With that said, there are simple aftermarket electronic controllers that will allow manual control of the center diff LSD action. That's not a great option because it would require constant attention, but it does allow some control. I think the kits sell for around $500-$600 US. Another option would be to rip out the DCCD center diff and put an STi heavy duty viscous center diff. I think that Subaru makes one now for the 6MT. Those are around $800-$1000 US.
__________________
Mychailo
:: 2006 Silver Mitsubishi Evolution 9, E85, 34 psi peak, 425wtq/505whp DJ ::
1995 Laguna Blue SVX L AWD 5MT (sold)

Visit my locker

SVX Mods: ND iridium spark plugs, Impreza RS fpr, afr tuned to 13.2:1 using a custom MAF bypass, custom exhaust, WRX 5MT w/ STi RA 1st-4th gear & stock WRX 5th gear, Exedy 13 lb flywheel & Sport Clutch, STi Group N tranny & engine mounts, urethane spacers in rear subframe, rear diff mounts, and pitch stopper, SVX Sport Strut Springs (185f/150r), custom 19 mm rear swaybar, urethane swaybar mounts, Rota Torque 17x8", 225/45-17 Proxes 4 tires, Axxis Deluxe Plus organic brake pads.
Reply With Quote
  #18  
Old 07-18-2006, 06:44 PM
dynomatt dynomatt is offline
Registered User
 
Join Date: Apr 2006
Location: Canberra...Capital of Australia
Posts: 883
Registered SVX
Thanks Mychailo. That's interesting regarding the DCCD controller. My information (possibly incorrect) was that, in the absence of a controller, they defaulted to a viscous centre with a 35:65 split. Not an open centre. I've done one gravel rally stage with an open diff and it was diabolical!!! Never again.

Might need to check that out. I had noticed aftermarket controllers for $149 USD no Ebay. Seemed to just be a knob which changed the lock from not much to a bit. But then it would also be handy to be able to switch it off (ie, go to an open diff when I pull on the handbrake (ebrake to you guys)).

Viscous ones were available from memory. In fact, there's a guy from VA who has a Forester box which is viscous, but has very tall ratios (like top gear and revs for the SVX would put it at over 360km/h!!)

Matt
Reply With Quote
  #19  
Old 07-18-2006, 08:45 PM
mbtoloczko's Avatar
mbtoloczko mbtoloczko is offline
sans SVX
 
Join Date: Sep 2002
Location: Richland, WA
Posts: 4,250
Send a message via AIM to mbtoloczko
It definitely does not default to a 35:65 viscous. The DCCD center diff consists of a planetary gear center diff that provides an intrinsic 35f:65r torque split and combines that diff with a magnetically actuated clutch connecting the front and rear drivelines. In absence of a controller, the clutch defaults to completely open.

$149 is definitely a good deal on a controller. Prices have come down signficantly.
__________________
Mychailo
:: 2006 Silver Mitsubishi Evolution 9, E85, 34 psi peak, 425wtq/505whp DJ ::
1995 Laguna Blue SVX L AWD 5MT (sold)

Visit my locker

SVX Mods: ND iridium spark plugs, Impreza RS fpr, afr tuned to 13.2:1 using a custom MAF bypass, custom exhaust, WRX 5MT w/ STi RA 1st-4th gear & stock WRX 5th gear, Exedy 13 lb flywheel & Sport Clutch, STi Group N tranny & engine mounts, urethane spacers in rear subframe, rear diff mounts, and pitch stopper, SVX Sport Strut Springs (185f/150r), custom 19 mm rear swaybar, urethane swaybar mounts, Rota Torque 17x8", 225/45-17 Proxes 4 tires, Axxis Deluxe Plus organic brake pads.
Reply With Quote
  #20  
Old 07-18-2006, 09:08 PM
dynomatt dynomatt is offline
Registered User
 
Join Date: Apr 2006
Location: Canberra...Capital of Australia
Posts: 883
Registered SVX
I wonder if it's just a simple case of a circuit with variable resistance applied over the DCCD wires?? Hmmm.
Reply With Quote
  #21  
Old 07-19-2006, 05:23 AM
dynomatt dynomatt is offline
Registered User
 
Join Date: Apr 2006
Location: Canberra...Capital of Australia
Posts: 883
Registered SVX
Mychailo,

Further research reveals that with the DCCD disconnected, it defaults to a 34:66 drive ratio. That tells me that the diff isn't open? If it was open, it might be 100:0 or 34:66 or even 50:50 depending on what it felt.

So I think it might not be viscous, but it certainly has the potentially to be able to be run without the DCCD controller

It also seems that this system was designed for rallying. My previous comments about wanting it to disengage when you pull on the handbrake - turns out it does this!!

This link (may require rego) has a scan of the manual relevant:

http://www.clubsub.org.nz/forums/vie...highlight=dccd

Cheers,
MAtt
Reply With Quote
  #22  
Old 07-19-2006, 01:18 PM
mbtoloczko's Avatar
mbtoloczko mbtoloczko is offline
sans SVX
 
Join Date: Sep 2002
Location: Richland, WA
Posts: 4,250
Send a message via AIM to mbtoloczko
Matt,

It can definitely be used for rally, but it works best when it can run in automatic mode rather than manual mode. To get it working in auto mode would require hooking up all the OEM sensors and controller. Not a simple task on a non-STi vehicle.

By "open" diff, I mean that the clutch will be completely disengaged. The plantary gears will still provide an intrinsice 35:65 (or 34:66) front/rear torque split, but with the clutch completely disengaged, if the front wheels or rear wheels loose traction, then all the power will go to the wheels that have lost traction.

With a manual controller, you'll be able to modulate the amount of clutch engagement which will not affect the torque split but will affect what happens when the wheels loose traction. With full engagement, the front and rear drivelines will be forced to rotate at the same speed. When there is partial engagement, there will be some limited amount of coupling between the front and rear drivelines.

This can be compared to an STi viscous center diff. The viscous center diffs all have a 50:50 front/rear torque split provided by a conventional spider gear center diff. The front and rear drivelines are then coupled using a viscous coupling system. With the viscous coupling, as one end of the car looses traction more and more, the viscous coupling provides a greater and greater coupling action between the front and rear drivelines. The coupling action is strong enough with the STi viscous center diffs that if you were, for instance, to break the prop shaft, the viscous coupler would lock up the center diff and you would be able to continue on front wheel drive alone.
__________________
Mychailo
:: 2006 Silver Mitsubishi Evolution 9, E85, 34 psi peak, 425wtq/505whp DJ ::
1995 Laguna Blue SVX L AWD 5MT (sold)

Visit my locker

SVX Mods: ND iridium spark plugs, Impreza RS fpr, afr tuned to 13.2:1 using a custom MAF bypass, custom exhaust, WRX 5MT w/ STi RA 1st-4th gear & stock WRX 5th gear, Exedy 13 lb flywheel & Sport Clutch, STi Group N tranny & engine mounts, urethane spacers in rear subframe, rear diff mounts, and pitch stopper, SVX Sport Strut Springs (185f/150r), custom 19 mm rear swaybar, urethane swaybar mounts, Rota Torque 17x8", 225/45-17 Proxes 4 tires, Axxis Deluxe Plus organic brake pads.
Reply With Quote
  #23  
Old 07-19-2006, 03:54 PM
dynomatt dynomatt is offline
Registered User
 
Join Date: Apr 2006
Location: Canberra...Capital of Australia
Posts: 883
Registered SVX
I see. I'm going to have to have a chat to the friend of mine who's running one, without a DCCD controller to understand what they've done.

I'll let you know.

Matt
Reply With Quote
  #24  
Old 07-19-2006, 06:18 PM
oab_au oab_au is offline
Registered User
Subaru Gold Contributor
 
Join Date: Mar 2001
Location: Coffs Harb, Australia.
Posts: 5,032
Significant Technical Input Registered SVX
Dccd .

From what I gather, the DCCD uses the same AWD set, that is in the Euro auto. The same compound epicyclic gear set, and clutch. As there is no hydraulics, the clutch must be operated electrically.

Without the clutch operating, it would be like the auto, to have the rear wheels spin. I guess the clutch could be operated, in line with the throttle and rpm. The more throttle, and the lower the rpm, the more clutch is applied. A controller that worked on these lines would be satisfactory.

Harvey.
__________________
One Arm Bloke.
Tell it like it is!

95 Lsi. Bordeaux Pearl, Aust. RHD.149,000Kls Subaru BBS wheels.
97 Liberty GX Auto sedan. 320,000Kls.
04 Liberty 30R Auto Premium. 92.000kls.
Reply With Quote
  #25  
Old 07-19-2006, 10:11 PM
mbtoloczko's Avatar
mbtoloczko mbtoloczko is offline
sans SVX
 
Join Date: Sep 2002
Location: Richland, WA
Posts: 4,250
Send a message via AIM to mbtoloczko
Harvey, I don't think its quite the same clutch. The DCCD clutch is magnetically actuated (probably via a large solenoid). Isn't the VTD clutch hydraulically actuated? Anyhow, it should be easy enough to operate the DCCD clutch. The harder part would be building a controller that operates based on sensor inputs.
__________________
Mychailo
:: 2006 Silver Mitsubishi Evolution 9, E85, 34 psi peak, 425wtq/505whp DJ ::
1995 Laguna Blue SVX L AWD 5MT (sold)

Visit my locker

SVX Mods: ND iridium spark plugs, Impreza RS fpr, afr tuned to 13.2:1 using a custom MAF bypass, custom exhaust, WRX 5MT w/ STi RA 1st-4th gear & stock WRX 5th gear, Exedy 13 lb flywheel & Sport Clutch, STi Group N tranny & engine mounts, urethane spacers in rear subframe, rear diff mounts, and pitch stopper, SVX Sport Strut Springs (185f/150r), custom 19 mm rear swaybar, urethane swaybar mounts, Rota Torque 17x8", 225/45-17 Proxes 4 tires, Axxis Deluxe Plus organic brake pads.
Reply With Quote
  #26  
Old 07-20-2006, 07:06 PM
oab_au oab_au is offline
Registered User
Subaru Gold Contributor
 
Join Date: Mar 2001
Location: Coffs Harb, Australia.
Posts: 5,032
Significant Technical Input Registered SVX
Quote:
Originally Posted by mbtoloczko
Harvey, I don't think its quite the same clutch. The DCCD clutch is magnetically actuated (probably via a large solenoid). Isn't the VTD clutch hydraulically actuated? Anyhow, it should be easy enough to operate the DCCD clutch. The harder part would be building a controller that operates based on sensor inputs.
Yes I didn't mean the same exactly. I guess it has a magnetic energiser operating the clutch, by a Duty cycle signal like the VTD.

Does the box have two speed sensors fitted? Do you have a link to a cutaway of the box?

Harvey.
__________________
One Arm Bloke.
Tell it like it is!

95 Lsi. Bordeaux Pearl, Aust. RHD.149,000Kls Subaru BBS wheels.
97 Liberty GX Auto sedan. 320,000Kls.
04 Liberty 30R Auto Premium. 92.000kls.
Reply With Quote
  #27  
Old 07-20-2006, 10:04 PM
Trevor's Avatar
Trevor Trevor is offline
Registered User
 
Join Date: Feb 2002
Location: Auckland, New Zealand
Posts: 5,223
Registered SVX
As I understand it the best rally drivers use a manual control, usually operated by the navigator on instruction from the driver, who has, or should have, his hands full. This is a real advantage which must be taken up. Anything fixed or automatic is for the slow group.
__________________
Trevor, New Zealand.

As a child, on cold mornings I gladly stood in cowpats to warm my bare feet, but I detest bull$hit!
Reply With Quote
  #28  
Old 07-21-2006, 11:22 PM
TomsSVX's Avatar
TomsSVX TomsSVX is offline
Maniac modifier
 
Join Date: Dec 2003
Location: Branchburg, New Jersey
Posts: 15,489
Registered SVX Classic SVX
For a rally car the cheap controllers on Ebay are more than sufficient. They will allow for adjustability of the diff without complete loss of locking. For a street car they are a very different case.

Harvey, there are no more than one speed sensor in the 6mt and it is used for the speedo the auto controller from the factory more or less makes it a limited slip center diff but when it needs to give way for being driven on the street it will allow it without much effort. I am sure the rotational readings from the ABS sensors give the controller a good idea of what it is doing.

Tom
Reply With Quote
  #29  
Old 07-23-2006, 01:35 AM
oab_au oab_au is offline
Registered User
Subaru Gold Contributor
 
Join Date: Mar 2001
Location: Coffs Harb, Australia.
Posts: 5,032
Significant Technical Input Registered SVX
Quote:
Originally Posted by TomsSVX
For a rally car the cheap controllers on Ebay are more than sufficient. They will allow for adjustability of the diff without complete loss of locking. For a street car they are a very different case.

Harvey, there are no more than one speed sensor in the 6mt and it is used for the speedo the auto controller from the factory more or less makes it a limited slip center diff but when it needs to give way for being driven on the street it will allow it without much effort. I am sure the rotational readings from the ABS sensors give the controller a good idea of what it is doing.

Tom
Thanks Tom, it looks to me, that the factory controller, operates the Limited Slip clutch, the same as the TCU in my car controls the VTD clutch.

The differences would be that the Controller, either, it can't see wheel spin, or it uses the ABS,as you suggest. Or it just anticipates it, by throttle and speed. The thumb wheel would just raise, or lower the controllers signal.

I reckon that you could trick a SVX TCU into running it in the same mode. Without the two speed sensors, it could not respond to wheel spin. That would be up to the driver.

It would just run, using the throttle, engine rpm and road speed, to do the same auto action. It would just need a thumbwheel to offset the throttle signal, to alter the level of the action. Just depends on that the signal level to the magnetic clutch is.

Maybe Matt could try it.
Harvey.
__________________
One Arm Bloke.
Tell it like it is!

95 Lsi. Bordeaux Pearl, Aust. RHD.149,000Kls Subaru BBS wheels.
97 Liberty GX Auto sedan. 320,000Kls.
04 Liberty 30R Auto Premium. 92.000kls.
Reply With Quote
  #30  
Old 07-25-2006, 01:08 AM
-JJ-'s Avatar
-JJ- -JJ- is offline
Endangered Species
 
Join Date: Jun 2005
Location: Sydney, NSW
Posts: 579
Send a message via MSN to -JJ-
Matt... Im still waiting on a reply from japan, sorry for the delay, will post as soon as i hear something
__________________
1992 Pearl / Black SVX

removed intake silencer, k&N pannel filter, trans cooler, 94 JDM 4eat, Noltec front swaybar mounts, Motorsport D&S disks with EBC Greenstuff pads
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 -6. The time now is 05:56 AM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2024, vBulletin Solutions, Inc.
© 2001-2015 SVX World Network
(208)-906-1122