steviep_

make a long story short
i didnt have an lsd i messed my diff up royaly and i needed a new one thought i might as well get an lsd
it was supposed to be clutch which my impression was better but the one they were gonna put it was broken so they got me one out of an 89 which i believe is a viscous
which is better and why
thank you

steviep_

anyone?

pd_day

iTrader: (6)

what are you using the car for?

Rxmfn7

iTrader: (4)

Clutch is better for about anything, the only real advantage to viscous is that it wont wear out like a clutch type will.

RETed

Clutch-type locks up faster - most people want this.&nbsp The viscous-type locks up more "softer".&nbsp The stock Mazda clutch-types usually wear beyond use within 50k miles, this means most FC's still running them probably have very worn units that don't work correctly.&nbsp As Rxmfn7 mentioned, the viscous-types don't wear out, but they are highly sensitive on diff fluid condition...



-Ted

twistedriver

How about gear type diff? ON this month's sport compact they talk about LSDs and the gear type sounds good. If i am not wrong gear type LSD isn't a real LSD. Is more like a torque bias mech. They do not require special fluid and they don't wear out. They engage very smooth. The only bad thing about gear type is that they don't do good burn outs, they tend to spin one wheel is the traction differents is toooo big. I think they also fit in your stander housing.

RETed

When I hear "gear-type" or "helical gear LSD", I think TorSen.&nbsp Are we on the same page?&nbsp The Torsen has the most linear lock-up characteristics than all other LSD's; road racers love them.


-Ted

jetfire76

so you agree Torsen diffs, like the one on FDs, are generally better than the clutch type? i always thought so, which is why i just got one from a 99 jspec FD to put in my AE

Ni5mo180SX

id say Torsen followed closely by clutch type.

JagdStealth

An FD Torsen dif will fit in the FC housing?

DomFD3S

The FD diffs are torsen type. However, if you notice, the aftermarket diffs for them are clutch type.

The reason is, while the torsen type is a more advanced design, the clutch type will hold more power. (This is what I am told by KAAZ).

Personally, I like the clutch type. Despite the fact that it wears out over time, I like the fact that you can actually adjust the clutch plates to determine a given pickup/lockup point. (This is true for KAAZ and OS Giken).

JagdStealth

Clutch type will hold a lot more power. Torsen is good for road racing simply beacuse of the way it engages and for instant traction, but for all other forms of racing where super high HP is involved , a clutch type is much better since it holds so much more power.

Cheers!

FD torsen will fit in a TII diff case / pumpkin

FD torsen will break easily if you drag race a lot and launch hard. Ask vosko

CRXtoRX7

Can you/how hard is it to rebuild a clutch type? I have a TII motor with na rear(no lsd) and if I got a clutch-type, I doubt it would be in good condition.

SupraDoom7

This was taken off a Supra website:
LSD Technology: Open Differentials vs. Clutch Type LSDs vs. Torsen LSDs
There are basically 3 types of differentials: an open differnential, the clutch type limited slip, and the torsen type limited slip.

Open DIfferential
This is the basic differential. The sides of the axle are coupled via gears. The speed of both halves will add up to a constant. However, the ratio from one side to the other is completely free. Torque will follow the path of least resistance.

Advantages:
Cheap, simple and light.
Doesn't cause over steer.
Never wears out.
Disadvantages:
If one wheel looses traction, it receives all power and the other wheel stays fixed (due to the greater force of static friction). The car will not accelerate well (if at all).

Clutch Type Limited Slip
The axle halves are linked with a set of gears like the simple differential. However, they are also linked by a set of clutches. The clutches will exert an extra force to try and turn the wheels at the same speed. The rule about the speed adding to a constant still applies.

Advantages:
Both wheels will try to turn in the same direction and at the same speed even when there is little or no traction.

Some force (relative to the amount of friction between the clutches) is applied to both wheels even if one wheel is spinning free. For example, if one wheel is in mud and the other on asphalt, the wheel that is on asphalt will receive some of the power and the car can move.

Disadvantages:
Causes over steer in corners (due to the LSDs attempt to keep the wheels spinning at the same speed) even when coasting.

Clutches can wear out.

Torsen Type Limited Slip
A torsen limited slip differential uses a set of helical gears to limit slip between the wheels. When no power is applied the wheels may spin independent as they do in a open differential. When power is applied the torsen LSD attempts to equalize the power application.

Advantages:
Both wheels will try to turn in the same direction and at the same speed as long as both wheels have some resistance (are not completely free).

Does not cause over steer when no power is applied.

Never wears out.

Disadvantages:
If one wheel is free (e.g. off the ground) it will receive all the power and the other wheel will receive 0 power.

Conclusion
For open road applications and auto-x, the torsen LSD is the best. However, the clutch type LSD is a very good unit for street and strip use also. For pure drag cars (i.e. those that are trailed to the drag strip and only drag race) a welded open differential may be the best choice. It is lighter and simpler and when welded will deliver equal power both wheels at all times.

RETed

Yes, the FD Torsen drops into the stock FC Turbo II rear diff.&nbsp We have a 1990 Turbo II running the stock FD Torsen right now.&nbsp It's set-up as a drift car, but it isn't making more than 300hp right now.


-Ted

rotard

Regarding SupraDoom's above post:

I have an open diff currently, but understood that an LSD would produce UNDER, not OVERsteer. (Inside wheel is lighter while cornering, so with open diff outside wheel receives more power; with LSD both wheels are powered, push from inside = harder to turn?)

So with LSD you slow down more going in and make up time with quicker acceleration thru apex and out?

RETed

Good question...

It depends.

There are different types of LSD's, and the Japan manufacturers use "1-way, 1.5-way, and 2-way" to describe their lock-up characteristics.

1-way - locks up only accelerating
1.5-way - locks up accelerating; locks up partially on decel
2-way - locks up accell and decel

Dak

The diff in Sport Compact Car was a Quaife.It is of the Helical type.How does the viscous compare to the clutch type and torsen.

rotary>piston

Clutch is better for performance, but the viscous lasts much longer. The torsen is best if it weren't for the fragility of it. That sudden lock up that takes place in them isn't too good for the gears.

RETed

I've done this before, but to those who never saw the first one...



This is lock-up versus slip characteristics on each LSD type.

WARNING:&nbsp The account will be deleted on 2 weeks from now.


-Ted

banzaitoyota

"WARNING: The account will be deleted on 2 weeks from now."

What account???

steviep_

so as for the s4 and s5 differentials
are they 1 way , 1.5 way, or 2 way?