Diffs - FWD LSD set to 1.5 or 2 Way - How to tell

[neo]

Question

If one has a TRD Plate type diff in a FWD vehicle, without pulling the gearbox apart how can you tell how its been set.

Mine should be set to 1.5 WAY, which I'd assume, if I stopped one wheel from turning, I should be able to turn / slip one wheel in reverse easier than to 'slip' the wheel in a forwards direction.


If it was set 2 WAY I'd assume it would be equally as hard to slip the free wheel in both directions.


And then, I assume most FWD are set to 1.5 WAY, what would be the advantage / how would it behave differently on the track should it be set to 2 WAY

Thanks

[rx7guy]

I dont know about seeing how its setup, but I wouldnt think you could slip by hand either way.

If you have a 2way on a FF you will likely get horrible understeer. 2way is only for drifting when you are wanting to slip the rear wheels into a corner.

[rollaholic]

yeah i'd have thought the way it drives would be a dead giveaway

[Truenotch]

The ".5" is measured on decel... So you could slam it in a low gear from high speed and see what marks it leaves .


Are you worried that yours is set to 2way Neil?

[iOnic]

Power into a corner and then lift off and see what happens.

[85AW20v]

Have a look at this post I did a while ago....

http://forums.toyspeed.org.nz/viewtopic.php?t=70368

It's in Tech FAQ under LSD info.

[TRD Man]

A TRD plate LSD should come new in the 1.5 way setting so you'd expect most cars would have it fitted this way. We adjusted every one we used to 2 way and advised most customers to do the same.

I don't believe there is any certain way to test without removing the unit.

[Mr Ree]

A TRD plate LSD should come new in the 1.5 way setting so you'd expect most cars would have it fitted this way. We adjusted every one we used to 2 way and advised most customers to do the same.

I don't believe there is any certain way to test without removing the unit.

Do you mean all your customers FWD cars too? I would have expected a FF to be pretty horrible to drive in 2 way mode due to the understeer issues already mentioned?

[TRD Man]

Yes FWD. However I am talking about motorsport use cars rather than road cars.
And, no, I don't accept that the car neccessarily understeers significantly more on the 2 way than the 1.5 way.
Certainly when the diff is tightened up that'll happen.
On our own car we had the diff shimmed up almost to the point of being locked and it did require an 'aggressive' cornering style.

We had a spate of ramp breakages in customers cars when used in the 1.5 way setting which didn't occur in 2 way mode. TRD Japan took some convincing that there was an issue and eventually supplied us with a box of spare ramps but it is not a part than can be bought separately so we advised rally customers, particularly, to put them in 2 way before installation.

[tsoob]

A TRD plate LSD should come new in the 1.5 way setting so you'd expect most cars would have it fitted this way. We adjusted every one we used to 2 way and advised most customers to do the same.

I don't believe there is any certain way to test without removing the unit.

Do you mean all your customers FWD cars too? I would have expected a FF to be pretty horrible to drive in 2 way mode due to the understeer issues already mentioned?

My diff must be one of the most aggressive ones out there, I dont really suffer from understeer unless really really giving it heaps thru a corner.. As far as we know its a cusco 2way.