fireballs gs400

Worm-gear Torsen-type LSD, 3.769 Ratio (13 teeth pinion, 49 teeth ring): Standard differential for 93-96 TT automatic transmission Supras.

is that the one i want for best performance.

tomtnc

I think the 3.769 ratio will offer optimal performance for the GS4. It is debatable whether or not the worm gear type of 93-96 is "better" than the helical gear type of 97-98. I would take either at this point if I found the right deal.

These differentials are not that plentiful in the "used" market right now. Expect to pay $400-$600 used and $1500 new. Furthermore, I've found most sellers are not wiling to remove the differential cover to confirm LSD and ratio and send pictures. If they are unwilling, this means they probably have something to hide. As you can see from the specs / application list, there is a wide variety of diffs available for the MKiV Supra so it would be easy to receive a diff other than what you paid for. Buyer beware!

JZS14SEVEN

just cause you don't know how to test a TorSen.... doesn't mean you can't test for one...
and a TorSen is NOT a L.S.D.

u gotta drive the car to see the motion the car takes, between the types of diff's

bitkahuna

iTrader: (20)

Really cool page on Torsen differentials.

http://www.globalwest.net/torsen_tra...fferential.htm

bitkahuna

iTrader: (20)

"Torsen-style Limited Slip Differential (LSD)" from Rod Millen's web site...

http://www.rodmillenstore.com/gs_400/diff.htm

redgs4

Here's a link to a Torsen differential whitepaper,
http://auto.howstuffworks.com/framed...ferential.html

From the How Stuff Works Site...

The Torsen (from Torque Sensing) works as an open differential when the amount of torque going to each wheel is equal. As soon as one wheel starts to lose traction, the difference in torque causes the gears in the Torsen differential to bind together. The design of the gears in the differential determines the torque bias ratio. For instance, if a particular Torsen differential is designed with a 5:1 bias ratio, it is capable of applying up to five times more torque to the wheel that has good traction. ...However, if one wheel loses traction completely, the Torsen differential will be unable to supply any torque to the other wheel. The bias ratio determines how much torque can be transferred, and five times zero is zero.

Zexel Torsen, Inc, http://www.torsen.com/, the maker of the torsen differential never mentions limited slip but rather torque distribution. While JZS14SEVEN may technically be correct and is certainly in agreement with Zexel propaganda, a torsen differential provides the same end function as an LSD.

JZS14SEVEN

so nice of the peoples at RMM to OverSimplify things for Lexus owners...
a "Torsen Style L.S.D."... "Standard Marketing Hype"
RMM has been racing enough knows its not a LSD.(i hope)
But how many LEXUS owners know the difference between a "Limit Slip Diff" and a "Torsen diff"?
most people only know open, locked, L.S.D.
and finally.... who's making money???

know what your buying.. before you buy it
better yet know what you want.. then look how to get there

///MDex

Who cares what its called?! Call it a cow-chip for all I care, as long as it provides me better traction and performance.

Most here know the difference between LSD and Torsen diff, but there are only a few available to us, so we collectively refer to them as LSDs. Chill out.

Wait, wait, wait - what would you rather we say, "traction adding devices"? Would that be OK with you?

jmecbr900

I have been doing research on this subject myself since a "mechanic" told me in conversation that my GS400 had LSD because ALL GS's HAVE them. I didn't believe him, but based on the "tests" described here, it may. Both wheels turn in different directions when jacked up.

I don't believe I do have it, but I also don't believe that some of these "tests" are accurate ways to tell either. Yes, they probably do what a true LSD does, but does that mean that it IS an LSD....doubtful. I highly doubt that some of the smarter CL members would go and spend good money on true LSD's unnecessarily.

I also agree with Dex...no matter what it's called, it still nets the same results. We really shouldn't split hairs about it.

redgs4

All GS's have electronic traction control which functions by applying brakes and/or reducing throttle -- keeps the car stable and pointed in the right direction but sucks for speed related activities. Many members [mine was installed today] are installing mechanical LSD's to get the power to the ground without reducing the power to the ground.

///MDex

SurVEY SAYS:
[sound from Family Fued buzzer]

JZS14SEVEN

I'm not in agreement with Zexel propaganda, i do agree with much of their FACTS..
of course they do not mention TorSen equiped vehicle "sacrafices" in their product advertisement/promotion.

end function same as a L.S.D.??
before you meet that end the TorSen redistributes power...
after you meet that end a L.S.D. starts working...
some difference in how they work and what they do..

going through a turn the timing/sequence of events changes according to what your car does best.
its up to the driver to understand when/where your advantages/disadvantages are...
only then will a driver be able to make use of what he's got.

redgs4

I'm not an expert, but I did stay at a Holiday Inn sometime in the past.

Yes, the torsen redistributes power and does so dependent upon the torque bias ratio of that particular unit. The key is the statement that the torsen can send a multiple of torque from the wheel that is slipping to the wheel that has traction -- and that zero traction means your multiple of redistributed torque is zero. As long as there is SOME traction the torsen functions much like an LSD, enough so that they are marketed and sold to the masses as an LSD.

Regarding the driver understanding and taking advantage of the strenghs and weaknesses of his car, well of course -- no disagreement on my part. Even with clutch type LSD's there are terms like 1-way, 2-way and now 1.5 way [the ATS LSD I installed is a 1.5 way -- thanks guru], each which affects the line a car can best take as it goes through a corner.

So JZS14SEVEN, you are right but it's a hollow victory as everyone will still undoubtedly use the term LSD to refer to the torsen type differential.