ae86 diff

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jakes_hachiroku
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ae86 diff

Postby jakes_hachiroku » Wed Jul 15, 2015 1:37 pm

Ok guys. here it comes, get out your pitchforks and try not to bash your keyboards in lol.
Reason i started off with that is because this is a very controversial topic. so you ready yet?
HELICAL LSD. ik, ik! but every forum is the same asshole saying simply... "THERE BAD"
and thats it lolol but doing the research it looks like when the tires start to slip it locks them both up instead of spinning just one. which with drifting isnt that what you want??? oh yea this is a drift question BTW ha.
but i read yea its not verry good for drifting and all that from people who probs just drift in forza which isnt a bad thing i guess thats my jam!
BUTTTTT then i see this!
https://www.youtube.com/watch?v=QzZ7Ad3DvCg
he drifts fine with a helical. yea i can almost guarentee a clutch diff is better but for the low budge guy who doesnt wana weld but still wants some slide in there daily. wouldnt this be a perfect drift diff like in the video?? any thoughts!?

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jondee86
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Re: ae86 diff

Postby jondee86 » Wed Jul 15, 2015 10:03 pm

Wikipedia says this (and the Torsen is a helical differential)...
Other current users of the Torsen limited-slip differential include the
Toyota GT86/Scion FR-S and the Subaru BRZ.

The first Ford company vehicle to use a Torsen differential was the 2002
Ford Ranger FX4, renamed in 2003+ years to FX4 Level II, all of which used
T-2R in the rear differential only. Starting in 2012, the Ford F-150 SVT Raptor
uses a front Torsen differential and the Ford Mustang Boss 302 uses a rear
Torsen differential.

Toyota Altezza (sold in U.S. and Canada as Lexus IS200 and IS300) came
with a torsen differential. For Lexus models it was available as an option
only on manual transmission with the sport package, while the Toyota Altezza
had it standard on all manual transmission SXE10 models (with the 5th-
generation Beams 3S-GE engine and J160 6-speed manual transmission)

And of course there are many more performance orientated vehicles that
use Torsen diffs, so it is hardly a budget item. It is in those cars because it
does a good job of maximising traction under varying conditions.

The actual theory of how a Torsen diff works is kind of difficult to understand
but this explanations from Wiki pretty much covers it...
When attempting to turn with a torque sensitive differential, the outer wheel
will need to rotate quicker relative to the differential, and the inner wheel will
rotate slower than the differential. Friction in the differential will oppose motion,
and that will work to slow the faster side and speed up the slower/inner side.
This leads to asymmetric torque distributions in drive wheels, matching the TBR.

Cornering in this manner will reduce the torque applied to the outer tire, leading
to possibly greater cornering power, unless the inner wheel is overpowered (which
is easier to do than with an open differential). When the inner tire (which has
less traction due to weight transfer from lateral acceleration) is overpowered,
it angularly accelerates up to the outer wheel speed (small percent wheel spin)
and the differential locks, and if the traction difference does not exceed the
TBR, the outer wheel will then have a higher torque applied to it. If the traction
difference exceeds the TBR, the outer tire gets the tractive torque of the inner
wheel multiplied by the TBR, and the remaining applied torque to the differential
contributes to wheel spin up.

Torque Bias Ratio (TBR) When a Torsen has a 3:1 TBR, that means that one side
of the differential can handle up to 75% while the other side would have to only
handle 25% of applied torque.

What this means in the drifters world is that the Torsen diff can make it more
difficult to get both rear wheels spinning compared to a "locking" differential,
spool or welded diff. This is what makes them BAD to the uneducated :) But
as you have pointed out, it is not impossible to drift a Torsen.

Cheers... jondee86
The reasonable man adapts himself to the world; the unreasonable one
persists in trying to adapt the world to himself. Therefore, all progress
depends on the unreasonable man.

jakes_hachiroku
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Re: ae86 diff

Postby jakes_hachiroku » Thu Jul 16, 2015 6:07 am

yea that makes good sense my friend! ive seen a few videos describing what hapens in there with the worm gears and what not and it looks like as long as one wheel starts slipping it will lock up both. so as long as you can get one spinning out with torqueit will lock up both sides. so yea you have to know how to trick it to lock up i guess. i think for the sake of experiment im guna put one in my 86 when i get the motor back together in the next few days. i wont be able to drift it for a little bit because ill have to brake in the motor but i deff wana feel it for myself so i can further share with people exactly how it "feels".

Deuce Cam
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Re: ae86 diff

Postby Deuce Cam » Fri Jul 17, 2015 11:01 am

A torsen (like all helicals as afaik) will act like an open diff. if a tire comes off the ground (or close to).

I would do more research because the consensus is they're not ideal for a live axle car in general - more so if you're trying to drift.

jakes_hachiroku
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Re: ae86 diff

Postby jakes_hachiroku » Fri Jul 17, 2015 11:30 am

Deuce Cam.
yea when i get the motor back in the car im guna weld the diff for now. and when the time comes im guna put a tomei 2 way in there. should get the job done just right! haha
but i like bringing up this discussion to see what everyone knows and thinks about stuff like this.

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jondee86
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Re: ae86 diff

Postby jondee86 » Sat Jul 18, 2015 6:37 pm

Deuce Cam wrote:... the consensus is they're not ideal for a live axle car in general

Good point that :) The Torsen is typically factory fitted to cars with IRS rather than
live axle rear ends. With IRS the wheels are more likely to stay on the ground due to
bump on one wheel not having any effect on the other wheel (as it does with a live
axle). So yeah, better to tread the well worn track on this one :)

Cheers... jondee86
The reasonable man adapts himself to the world; the unreasonable one
persists in trying to adapt the world to himself. Therefore, all progress
depends on the unreasonable man.