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
  #46  
Old 11-29-2007, 10:54 PM
Trevor's Avatar
Trevor Trevor is offline
Registered User
 
Join Date: Feb 2002
Location: Auckland, New Zealand
Posts: 5,223
Registered SVX
Quote:
Originally Posted by ridered777 View Post
Sorry to bring this thread back from the dead...

But I have a question which no one asked, and I'm surprised it didn't come up.

I hear from... someone... *Cough*David(Seraphinwolf)*Cough* that all Subaru trannies have this neat little thing where if you put the gear selector in "3", it over-rides the usual torque split between the front and rear wheels and makes it CLOSER to 50/50. He said the exact number of slip varies by tranny/car I think...

Any thoughts or ideas? I've never seen anyone say anything about it, and I've done a few tests in my car in "low traction situations", and though I don't THINK it's changing the split (that is, when the wheels slip, then AWD split kicks in, giving more power to rear wheels), it's obviously (as I'm sure Trevor will point out ) not a reliable scientific method by any means.

Craig
Greetings Craig,

I have never heard of this. it will be interesting to find out if anyone else has information on the subject.

Off the cuff, I would sence that this could be no more than a rumor.
__________________
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
  #47  
Old 11-29-2007, 10:59 PM
Trevor's Avatar
Trevor Trevor is offline
Registered User
 
Join Date: Feb 2002
Location: Auckland, New Zealand
Posts: 5,223
Registered SVX
Quote:
Originally Posted by Wikedjuggalo View Post
What about FWD cars? what effect does this have? Does it matter if driving in 3 will do anything? I mean I guess the same thing? Also I don't do this as I usually get over 50 often but damn stop lights get in my way J/k.
The same automatic transmission is involved, so that the same factors apply for FWD models.
__________________
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
  #48  
Old 11-30-2007, 12:18 AM
Hondasucks's Avatar
Hondasucks Hondasucks is offline
Subaru Technician
 
Join Date: Aug 2007
Location: Vancouver, WA
Posts: 1,512
Send a message via AIM to Hondasucks Send a message via MSN to Hondasucks Send a message via Yahoo to Hondasucks
Registered SVX
I heard that torque split thing, but with 1 and 2 range, not 3.... Not sure though (I know my car seems to launch better if I take off in 1st or 2nd and slap it into D as soon as I get going)

As far as not driving around town in Overdrive, I heard to put it in 3 in town because that's one less shift the tranny has to make, and if you are doing stop and go driving, to leave it out of overdrive. I heard once you are doing 45MPH or more, sustained, to put it in overdrive.. I usually put mine in 3rd when I'm driving around town, and sometimes if I'm climbing a steep hill, I'll drop down to 2nd too keep it from hunting between 2nd and 3rd.

As for manual mode, it does nothing in D range, in 1 or 2 range it will hold the transmission in 2nd gear, and in 3 range it will shift 2nd to 3rd, but won't go to 1st, and won't go into overdrive.
__________________
1992 SVX LS-L #1222 Pearl White
1987 GL Turbo wagon, 5 lug conversion, D/R 5 speed (Rice killer)
1992 Dodge Ram 4x4 diesel (car hauler)
1968 Dodge Polara convertible (Camaro killer)
1990 Toyota Corolla FWD auto (330,000 mile grocery getter)
1986 VW Jetta
Reply With Quote
  #49  
Old 11-30-2007, 02:42 AM
svxistentialist's Avatar
svxistentialist svxistentialist is offline
Jersey Girl
Alcyone Gold Contributor
 
Join Date: Mar 2001
Location: Ireland
Posts: 8,270
Send a message via Skype™ to svxistentialist
Registered SVX
Quote:
Originally Posted by ridered777 View Post
Sorry to bring this thread back from the dead...

But I have a question which no one asked, and I'm surprised it didn't come up.

I hear from... someone... *Cough*David(Seraphinwolf)*Cough* that all Subaru trannies have this neat little thing where if you put the gear selector in "3", it over-rides the usual torque split between the front and rear wheels and makes it CLOSER to 50/50. He said the exact number of slip varies by tranny/car I think...

Any thoughts or ideas? I've never seen anyone say anything about it, and I've done a few tests in my car in "low traction situations", and though I don't THINK it's changing the split (that is, when the wheels slip, then AWD split kicks in, giving more power to rear wheels), it's obviously (as I'm sure Trevor will point out ) not a reliable scientific method by any means.

Craig
Craig

There is a small element of urban myth about this.

Like Trevor says, we have never heard from any source that the torque split front/rear will go to 50/50 in 3 range only.

So far as I understand it, the computer [aka TCU] control of F/R torque split happens in all four ranges, 1,2,3,D

It is, however, close to the truth for US cars with the electric rear clutch. For US cars in normal driving, torque is split 85% F and 15% R. Under poor traction the computerised torque control program can vary the split ratio so that more torque is sent to the back,say if the front wheels were losing traction. The maximum split it can adjust up to is 50%F and 50% R. Just like *cough* Seraphin *cough* said

So what Wolf says is close to the truth, except it is not 3 range only, and, it is not a "switch" but is varied by computer over a range from 15% rear torque up to 50% rear torque.

Euro and Japanese boxes are different. Standard torque for them is 35% F and 65% R. Again, the computer varies the split in low grip conditions, in this case increasing the front torque through the range from 35% to 50% as the situation demands.

Joe
__________________
Black Betty [Bam a Lam!] '93 UK spec, still languishing Betty
Jersey Girl Silver '92 UK [Channel Isles] 40K Jersey Girl @ Mersea
Candy Purple Honda Blackbird Plum Dangerous
White X2 RVR Mitsubishi 1800GDI. Vantastic

40,000 miles Jersey Girl
Reply With Quote
  #50  
Old 11-30-2007, 02:48 AM
svxistentialist's Avatar
svxistentialist svxistentialist is offline
Jersey Girl
Alcyone Gold Contributor
 
Join Date: Mar 2001
Location: Ireland
Posts: 8,270
Send a message via Skype™ to svxistentialist
Registered SVX
Quote:
Originally Posted by Hondasucks View Post

As for manual mode, it does nothing in D range, in 1 or 2 range it will hold the transmission in 2nd gear, and in 3 range it will shift 2nd to 3rd, but won't go to 1st, and won't go into overdrive.

This is a very good description of Manual, quite correct.

It also does another thing; it stops the gearbox accessing the Power shift map. It is something you could try out; put the gear selector in 3 with manual switched on, and bury the loud pedal [in a safe place on the open road]. The car will accelerate, not a quick launch because it has skipped 1 range, then rapidly gaining speed. At no time will you see the Power light come on, because it can't use that shift map while manual is operating.

Joe
__________________
Black Betty [Bam a Lam!] '93 UK spec, still languishing Betty
Jersey Girl Silver '92 UK [Channel Isles] 40K Jersey Girl @ Mersea
Candy Purple Honda Blackbird Plum Dangerous
White X2 RVR Mitsubishi 1800GDI. Vantastic

40,000 miles Jersey Girl
Reply With Quote
  #51  
Old 11-30-2007, 06:16 AM
ridered777's Avatar
ridered777 ridered777 is offline
Finally HAS a 3rd pedal!!
 
Join Date: Feb 2007
Location: Nh, USA
Posts: 828
Send a message via AIM to ridered777 Send a message via MSN to ridered777 Send a message via Yahoo to ridered777
Thanks for clearing it up, Joe.

I know how the split works - I was trying to find a way to get the slip to be more even (really I'd like it to be rear-wheel bias...) WITHOUT spinning the tires. Because once you spin the tires, you've already lost traction.

Think of it as a passive vs. active system. Active kicks in when necissary (with regards to safety, airbags). However, a passive is always there (again, with regards to safety, something such as ABS or your setbelt even). I was attempting to find a way to make the car closer to 50/50 to PREVENT the tires from slipping, rather than having it happen after the tires are slipping.

This is why I was so curious about this supposed short-cut. Maybe I'll give 2 a try, Honda.

I know I can trasnplant a center diff and rear end from a Jap/Euro one. I'll put a 50/50 Cusco diff in when I convert to 5spd, but I was looking for something that could be possibly be nice and easy and not cost me any money.
__________________
-Craig

94 LSi 5spd Barcelona Red, 14Xk miles.

Full custom exhaust (Stebro cat-back, custom rest of the way forward) 8000K HID kit from Tom (SVXfiles), Energy Suspension front sway bar bushings, Non-Droopy visors, Race Concepts C/D + Dimpled Rotors, Axxis Ultimate pads,SS brake lines, Bontrager Works #009 (or something like that), stripped interior.

(up next) Full cage, fuel cell, 327 swap
Reply With Quote
  #52  
Old 11-30-2007, 06:40 AM
svxistentialist's Avatar
svxistentialist svxistentialist is offline
Jersey Girl
Alcyone Gold Contributor
 
Join Date: Mar 2001
Location: Ireland
Posts: 8,270
Send a message via Skype™ to svxistentialist
Registered SVX
Quote:
Originally Posted by ridered777 View Post
Thanks for clearing it up, Joe.

I was attempting to find a way to make the car closer to 50/50 to PREVENT the tires from slipping, rather than having it happen after the tires are slipping.

This is why I was so curious about this supposed short-cut. Maybe I'll give 2 a try, Honda.

I know I can trasnplant a center diff and rear end from a Jap/Euro one. I'll put a 50/50 Cusco diff in when I convert to 5spd, but I was looking for something that could be possibly be nice and easy and not cost me any money.
Ah yes, Craig, I see what you are at.

To do it properly it would be good, probably necessary, to change the software code in the TCU.

That would require reverse engineering the TCU, like what the guys are now doing to the ECU, and control the information written to the Roms. In theory I expect it is possible, but it is well outside my skillset.

Your best bet is installing a jdm gearbox, plus use the jdm TCU. And btw, the euro box with a jdm TCU will not work for you. You would need euro/euro or jdm/jdm, as the controllers are different.

Joe
__________________
Black Betty [Bam a Lam!] '93 UK spec, still languishing Betty
Jersey Girl Silver '92 UK [Channel Isles] 40K Jersey Girl @ Mersea
Candy Purple Honda Blackbird Plum Dangerous
White X2 RVR Mitsubishi 1800GDI. Vantastic

40,000 miles Jersey Girl
Reply With Quote
  #53  
Old 11-30-2007, 07:58 AM
PDSides PDSides is offline
Old Guy
 
Join Date: Mar 2001
Location: Reno, Nevada
Posts: 282
Hard to believe that we are 15+ years into SVX ownership and this topic is still being discussed. New wave of owners I suspect. Begs the question, will all previous posts become new again? One thing I notice different in these newer discussions of old topics, there is a higher level of technical expertise across the board. In the early years most SVX owners bought their new cars (or newer cars) with the idea of Subaru keeping them running. Now, there are more do-it-yourself owners, folks who know a lot about these cars. Out of necessity, I would suppose, since there are so few professional car care centers out there that know beans about the SVX. So, who wants to ask about the stamped letter "L" on some SVX wheels and not on others?
Preston
Reply With Quote
  #54  
Old 11-30-2007, 08:26 AM
svxistentialist's Avatar
svxistentialist svxistentialist is offline
Jersey Girl
Alcyone Gold Contributor
 
Join Date: Mar 2001
Location: Ireland
Posts: 8,270
Send a message via Skype™ to svxistentialist
Registered SVX
I have noticed the same Preston. I think it is the new batch of owners.

You see many giving the "do a search" reply when people ask some of the same old questions. However, I don't believe the search function is clever enough to go back all the way, and select the exact piece of information that you might want. It normally pulls up a huge string of hits.

This leads me to the conclusion that we really ought to do up a document [or a few documents] like the MacLaine FAQ that we all referred to way back.

It should be easy enough to predict the questions and problems that new or prospective owners will hit up against, and include answers to them in these descriptive documents.

Even better than that, we could "seed" the document with url links that members could click to go direct to solutions and other how-tos, suppliers and shops and maybe other on-line technical resources.

I have my own theory about the Ls, but I'll wait to see what the newer members think.

Joe
__________________
Black Betty [Bam a Lam!] '93 UK spec, still languishing Betty
Jersey Girl Silver '92 UK [Channel Isles] 40K Jersey Girl @ Mersea
Candy Purple Honda Blackbird Plum Dangerous
White X2 RVR Mitsubishi 1800GDI. Vantastic

40,000 miles Jersey Girl
Reply With Quote
  #55  
Old 11-30-2007, 08:42 AM
AlcyoneDaze's Avatar
AlcyoneDaze AlcyoneDaze is offline
<-- custom hood ornament
 
Join Date: Nov 2006
Location: NJ
Posts: 689
Send a message via AIM to AlcyoneDaze Send a message via Yahoo to AlcyoneDaze
Could it be L means they belong on the left side? don't mock me too badly, just a guess
__________________
1992 Pearl White/Black Onyx Subaru Alcyone SVX LS-L
Donating Forum Member In Good Standing
JDM 4.11 Geared Transmission
JDM 'ALCYONE' Rear Panel
JDM 'BOXER' Eingngine Cover
JDM 'SVX' Hood Badge
L-Edition Suede Rear Seats
Reply With Quote
  #56  
Old 11-30-2007, 10:33 AM
crazyhorse's Avatar
crazyhorse crazyhorse is offline
242,000 mi on oem trans
 
Join Date: Aug 2007
Location: Greeneville, TN
Posts: 1,111
Registered SVX
I drive mine in "3" around town & on the twisties. I get some engine braking in 3rd, but not any more than any other 3spd auto. Once I'm up over 60mph & I know I can maintain that for awhile, I use "D" I've done this in EVERY 4spd auto I've ever owned. THe car responds better in the lower gears, and it doesn't need to downshift but one gear to pass another car.
My Pinto, a 3spd "C4" auto I drive full manual. I up & downshift with the stick. The SVX I just stick in "3" & drive. Around here the half second wait for a lower gear can make for a TIGHT passing situation! In "3" the SVX downshifts RIGHT NOW!
__________________
[SIGPIC]http://www.subaru-svx.net/forum/image.php?type=sigpic&userid=5569&dateline=1207440 507[/SIGPIC]
Naught but by the grace of God
"42"
Current Stable By Age:
'89 Subaru XT6 Silver "Audrey" as in Hepburn
'96 SVX LSi #767Brilliant Red "Lil Red" Now on the front burner. Looking for a totalled, but running parts car.
Reply With Quote
  #57  
Old 11-30-2007, 02:53 PM
Trevor's Avatar
Trevor Trevor is offline
Registered User
 
Join Date: Feb 2002
Location: Auckland, New Zealand
Posts: 5,223
Registered SVX
Quote:
Originally Posted by svxistentialist View Post
Craig

For US cars in normal driving, torque is split 85% F and 15% R.

Euro and Japanese boxes are different. Standard torque for them is 35% F and 65% R.
Joe
I do not have US manuals. From what official source do the US figures originate?

Exactly how is there a torque split during normal driving when there is no wheel slip, and as I understand it, only a clutch involved in respect of torque distribution?

As a matter of interest the JDM split is actually, 36.4% F and 63.6% R and this is as a result of a gear ratio inherent within the centre diff.
__________________
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
  #58  
Old 11-30-2007, 03:40 PM
kwren's Avatar
kwren kwren is offline
Registered User
 
Join Date: Aug 2006
Location: washington state
Posts: 3,499
Slower than 45 mph??

[QUOTE=Hondasucks;512001] I heard once you are doing 45MPH or more, sustained, to put it in overdrive..

Why would anyone drive around town slower than 45 mph????

Sorry, Got it!
you are right of course! You are talking school zone!

Last edited by kwren; 11-30-2007 at 03:43 PM.
Reply With Quote
  #59  
Old 11-30-2007, 05:36 PM
Trevor's Avatar
Trevor Trevor is offline
Registered User
 
Join Date: Feb 2002
Location: Auckland, New Zealand
Posts: 5,223
Registered SVX
[QUOTE=kwren;512135]
Quote:
Originally Posted by Hondasucks View Post
I heard once you are doing 45MPH or more, sustained, to put it in overdrive..

Why would anyone drive around town slower than 45 mph????

Sorry, Got it!
you are right of course! You are talking school zone!
Why has Hondasucks post been taken out of context and denigrated? I am curious as to the exact reason for, and meaning inferred by this post.

Is it that this an unfortunate sick, sarcastic joke? How was the post worded prior to editing?

Does the author drive around in town at all time in excess of 45 MPH, irrespective of danger to others, unless a school zone is involved and detection is likely?

To be honest I am not confused, but am informed.

P.S. Joe, please back track to my earlier post.
__________________
Trevor, New Zealand.

As a child, on cold mornings I gladly stood in cowpats to warm my bare feet, but I detest bull$hit!

Last edited by Trevor; 11-30-2007 at 05:39 PM. Reason: P.S. Added
Reply With Quote
  #60  
Old 11-30-2007, 05:42 PM
NikFu S.'s Avatar
NikFu S. NikFu S. is offline
Takin tools to task
 
Join Date: May 2003
Location: A-town, Alaska
Posts: 7,280
Send a message via MSN to NikFu S.
Registered SVX
Quote:
Originally Posted by NikFu S. View Post
The way things are looking I'll probably need one soon.
Little did I know...
__________________
"That which can be asserted without evidence
can be dismissed without evidence."


'92 Dark Teal SVX LS-L, >146,000m
3 pedals, 5 speeds., restoration underway.
2012 Honda Insight, slow but cute.
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 02:49 AM.


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