2nd Generation Specific (1986-1992) 1986-1992 Discussion including performance modifications and technical support sections.
Sponsored by:

LSD for NA

Thread Tools
 
Search this Thread
 
Old 01-16-08, 03:08 AM
  #1  
Rotary Turbo

Thread Starter
 
driftingmyFC's Avatar
 
Join Date: Aug 2007
Location: A-Town, IL
Posts: 422
Likes: 0
Received 1 Like on 1 Post
LSD for NA

Does anyone know if there are aftermarket LSD for a s4 na instead of a TII rear end?
Old 01-16-08, 03:45 AM
  #2  
slo
registered user

iTrader: (1)
 
slo's Avatar
 
Join Date: Jan 2006
Location: San Diego
Posts: 2,469
Likes: 0
Received 0 Likes on 0 Posts
sure there is
Old 01-16-08, 03:54 AM
  #3  
Yo dawg, Im happy for you

iTrader: (2)
 
RyosukeD's Avatar
 
Join Date: Jan 2006
Location: Corvallis, Oregon
Posts: 574
Likes: 0
Received 0 Likes on 0 Posts
Yes.
Old 01-16-08, 08:13 AM
  #4  
RIP Mark

iTrader: (2)
 
YaNi's Avatar
 
Join Date: May 2006
Location: Dublin, OH
Posts: 657
Likes: 0
Received 1 Like on 1 Post
Whats wrong with the options available (miata torsen, S4 clutch, S5 viscous)?
Old 01-16-08, 09:37 AM
  #5  
Card-carrying Rotorhead

 
Unseen24-7's Avatar
 
Join Date: May 2006
Location: Quebec
Posts: 457
Likes: 0
Received 0 Likes on 0 Posts
Not to thread jack but how does the s4 NA LSD (GXL) compare to the s4 and s5 T2 LSD's, as well as that torsen miata one?
Old 01-16-08, 04:06 PM
  #6  
Unbereevable

 
caeya's Avatar
 
Join Date: Nov 2007
Location: Winfield, BC
Posts: 103
Likes: 0
Received 6 Likes on 4 Posts
the s4 is clutch type lsd and can be rebuilt, while the s5 is vicous. the miata torsen lsd is tougher and locks up faster.

Last edited by caeya; 01-16-08 at 04:25 PM.
Old 01-16-08, 04:23 PM
  #7  
The Silent but Deadly Mod

iTrader: (2)
 
Roen's Avatar
 
Join Date: Aug 2003
Location: NYC/T.O.
Posts: 4,047
Received 3 Likes on 3 Posts
um....no on the "torsen clutch LSD" characteristics. Try again.
Old 01-16-08, 08:55 PM
  #8  
Old Rotary Dog

 
wrankin's Avatar
 
Join Date: Feb 2003
Location: Durham, NC
Posts: 1,461
Likes: 0
Received 2 Likes on 2 Posts
Okay, I'll save you the cost of a search. There were two stock LSDs that came on a the NA FC. The clutch type (read the FAQ as to which models) and the viscous. The clutch type tended to wear out but could be rebuilt. The viscous was not as good, but tended to easier to maintain (new fluid). The early 90's Miata Torsen unit could also be swapped into the FC diff and was a prettty bomb-proof solution. Not as good (in some peoples opinion) as the clutch type, but better than the viscous and pretty much as bomb-proof.

I currently have an open diff in my FC track car and I seldom notice the difference. A good LSD would probably lower my lap times, but right now it's not the limiting factor (ie. I'm planning it for a future upgrade ).

-bill
Old 01-16-08, 09:07 PM
  #9  
The Silent but Deadly Mod

iTrader: (2)
 
Roen's Avatar
 
Join Date: Aug 2003
Location: NYC/T.O.
Posts: 4,047
Received 3 Likes on 3 Posts
The Torsen is usually preferred around a road course due to it's progressive lockup characteristics, rather than the abruptness of a clutch-type.
Old 01-16-08, 10:25 PM
  #10  
Lives on the Forum

 
Black91n/a's Avatar
 
Join Date: Sep 2003
Location: BC, Canada
Posts: 5,707
Likes: 0
Received 4 Likes on 4 Posts
The TII diffs are bigger and stronger, but that's not needed on an NA car, they don't have the power to need it. Don't bother with an S5 diff, the magic fluid inside that does the work will almost certainly be dead and it'll act as an open diff.

I like my torsen, it feels almost like the stock open diff, but still limits slip. It will act as an open diff if one wheel has little to no traction (on ice, gravel, in the air). Technically it's a torque biasing diff, not a limited slip in the traditional sense. They do not wear out though. A clutch type can handle those situations if it's not worn.
Old 01-16-08, 10:36 PM
  #11  
Dork

 
sniperstevedave's Avatar
 
Join Date: Sep 2006
Location: Cedar Rapids, Iowa
Posts: 125
Likes: 0
Received 0 Likes on 0 Posts
Check out Mazdatrix. They sell Kaaz clutch disk LSDs and recently started selling Torsen types as well. If you are going to drift your car continuously, then you may want a clutch type. If you are going to drive on the street at all, go with a torque bias (mechanical) type. The friction clutch types are noisy and abrupt, but can be adjusted for wear and so are good for abusive use like dedicated drifting. This is based off of the results of my own research into the matter, anyway. Find out the facts first hand and then make your choice is the best advice anyone can give.
Old 01-16-08, 10:51 PM
  #12  
Lives on the Forum

iTrader: (7)
 
Sideways7's Avatar
 
Join Date: Dec 2003
Location: Temple, Texas (Central)
Posts: 6,596
Received 9 Likes on 5 Posts
Originally Posted by Black91n/a
The TII diffs are bigger and stronger, but that's not needed on an NA car, they don't have the power to need it.
Not to mention the fact that its almost completely incompatable.
You would have to use the entire LSD and half-shafts from a turbo car, not to mention make a custom driveshaft. Or you could use a turbo tranny (including clutch/flywheel assembly) plus a turbo driveshaft in place of the custom driveshaft.
Old 01-17-08, 05:17 AM
  #13  
RX-7 DISCIPLE

iTrader: (1)
 
Ex-Eg-Driver's Avatar
 
Join Date: Nov 2007
Location: NorCal,California
Posts: 1,039
Likes: 0
Received 0 Likes on 0 Posts
S4 Gxl Lsd
Old 01-17-08, 10:32 AM
  #14  
Full Member

 
American Rice's Avatar
 
Join Date: Jun 2005
Location: Fort Saskatchewan, Alberta, Canada
Posts: 197
Likes: 0
Received 0 Likes on 0 Posts
lol have a 86 gxl diff in my garage right now not being used as I have a TII now
Old 01-17-08, 12:02 PM
  #15  
Full Member

 
uptotibet's Avatar
 
Join Date: Aug 2007
Location: Portland, OR
Posts: 147
Likes: 0
Received 0 Likes on 0 Posts
It depends on what you want to do. Personally I visited this yesterday.

If you are going to stay under 250hp stick with the non-turbo housing (NA and GXL) and get yourself a S2000 Torsen LSD for under $250. They are everywhere, check honda-tech and watch ebay carefully. You can also go the miata route, but those are more expensive and more fragile, two bads IMHO, hence not worth it.

If you are going to up the horsepower and go with 300,350,400 plus HP, then you need to switch to the Turbo housing, turbo axles, and strong mounts of some kind (mazdaspeed, hard, poly, faux-snubber, whatever). Into this pumpkin you add the FD torsen diff and a 4.3 or 4.1 gear set and you are ready to go.

For my track-beater / current daily driver I'm going to use: FD torsen diff, 4.30 gears, turbo axles, turbo housing, mazdaspeed mounts, floor mounted safety snubber.


I think this is the best solution for the money because clutch type diffs result in a locking situation which is not always optimal. Please don't read this wrong: It can be optimal, but for one it has to be tuned to what the car does, and thats just a real pain in the butt for a daily driver where the Torsen technology handles that junk for you. If you want oversteer, leave it to suspension and motor, not the driveline. Just my personal rant anyways.
Old 01-17-08, 12:27 PM
  #16  
Who Shot the Sheriff?

iTrader: (2)
 
Turbo II Rotor's Avatar
 
Join Date: Jan 2007
Location: Aurora, CO
Posts: 3,858
Likes: 0
Received 1 Like on 1 Post
ATS has a couple different lsd's for different applications. Road racing - carbon lsd, Drifting - deltaforce lsd and for street and strip go with the metal lsd.
Old 01-17-08, 01:55 PM
  #17  
Full Member

 
hiideruhiro's Avatar
 
Join Date: Dec 2007
Location: Chicago, IL
Posts: 73
Likes: 0
Received 0 Likes on 0 Posts
Using a torsen LSD how does it fair for drifting against a clutch type LSD? Why is vlsd always looked down upon? Is there any advantages to vlsd over torsen and/or clutch type? Sorry for thread jacking a bit, but the topic creator asked a vague question and it gave me ideas on which routes I have.
Old 01-17-08, 02:47 PM
  #18  
Lives on the Forum

 
Black91n/a's Avatar
 
Join Date: Sep 2003
Location: BC, Canada
Posts: 5,707
Likes: 0
Received 4 Likes on 4 Posts
Since when is the Miata torsen fragile? I'm pretty sure it's the same as the S2000 one, because why would they build two different ones that are entirely compatible, but one's better? They did build two different versions, the T1 and T2 types and I'm not talking about that, as both types can be gotten from Miatas.

For drifting you'll want a fairly tight clutch type to keep the wheels turning together, but you can use other types too.

VLSD's are looked down upon because they aren't servicable and the magic fluid in them breaks down with use and it'll eventually approximate an open diff. They're popular in OEM applications because they're very smooth.

For most people a Torsen is the best thing, but for drag or drift a clutch type is better. Sometimes in road racing or autocross people prefer a clutch type, but that's more just personal preference rather than one being superior.
Old 01-17-08, 03:48 PM
  #19  
Registered User

iTrader: (4)
 
dial8's Avatar
 
Join Date: Oct 2004
Location: Pacifica
Posts: 1,090
Likes: 0
Received 0 Likes on 0 Posts
Originally Posted by Unseen24-7
Not to thread jack but how does the s4 NA LSD (GXL) compare to the s4 and s5 T2 LSD's, as well as that torsen miata one?
Look here
https://www.rx7club.com/2nd-generation-specific-1986-1992-17/frequently-asked-questions-2nd-generation-rx-7-faq-fc-494667/
Old 01-17-08, 03:49 PM
  #20  
Registered User

iTrader: (4)
 
dial8's Avatar
 
Join Date: Oct 2004
Location: Pacifica
Posts: 1,090
Likes: 0
Received 0 Likes on 0 Posts
Originally Posted by caeya
the s4 is clutch type lsd and can be rebuilt, while the s5 is vicous. the miata torsen lsd is tougher and locks up faster.
Wrong

Originally Posted by Roen
The Torsen is usually preferred around a road course due to it's progressive lockup characteristics, rather than the abruptness of a clutch-type.
Right
Old 02-06-08, 07:34 PM
  #21  
Full Member

 
Ishibubu's Avatar
 
Join Date: Aug 2006
Location: Georgia
Posts: 237
Likes: 0
Received 0 Likes on 0 Posts
Are TII and NA LSDs different?
Old 02-06-08, 09:43 PM
  #22  
The Silent but Deadly Mod

iTrader: (2)
 
Roen's Avatar
 
Join Date: Aug 2003
Location: NYC/T.O.
Posts: 4,047
Received 3 Likes on 3 Posts
did you seriously just ask that?

yes, they are.
Old 02-07-08, 12:43 AM
  #23  
Lives on the Forum

 
Black91n/a's Avatar
 
Join Date: Sep 2003
Location: BC, Canada
Posts: 5,707
Likes: 0
Received 4 Likes on 4 Posts
Originally Posted by wrankin
The early 90's Miata Torsen unit could also be swapped into the FC diff...
One small correction: ANY 1.8 Miata Torsen will fit. The 94-97 cars got the T1 Torsen, the 99-05 cars got the T2 Torsen. Either one will fit, they'll act about the same, but they are a different design. The T1 is the same design as is sold by Quaife and others for different applications. The FD uses a T1. Basically the difference between the two is that on the T1 the worm gears run perpendicular to the half shafts, on the T2 they run parallel.

Info here: http://www.torsen.com/products/products.htm
Old 02-07-08, 07:54 AM
  #24  
Old Rotary Dog

 
wrankin's Avatar
 
Join Date: Feb 2003
Location: Durham, NC
Posts: 1,461
Likes: 0
Received 2 Likes on 2 Posts
Great info - thanks for the link. I didn't realize the later diffs were compatible. It would seem that the T1 unit would be preferable for a race car, unless the Miata T2 is actually a T2R. Does anyone know?

More importantly - does anyone know where I can score a Miata unit for under $400?

-b
Old 02-07-08, 09:03 AM
  #25  
The Silent but Deadly Mod

iTrader: (2)
 
Roen's Avatar
 
Join Date: Aug 2003
Location: NYC/T.O.
Posts: 4,047
Received 3 Likes on 3 Posts
If the T1 and the T2 are similar, why is the T1 more preferable in a race car?


Quick Reply: LSD for NA



All times are GMT -5. The time now is 09:06 AM.