What diff to get for f series diff?

[Mirko]

Have manage to get my hands on a F series housing and gonna build it for my AE86. Was thinking of getting a Eaton Detroit Truetrac Diff for it. Its going to be driven on the street and circuit racing NOT Drift.

Wanted to get peoples thoughts and any experiences with them or any other good diff's for them?

[LittleRedSpirit]

never used one and I think most people havent on here.

[Mirko]

Yeah haven't either but hear good things

[drift kid]

F series is hilux diff right? I'm looking at these options too for my hilux daily but I don't want the harshness of a tru trac, I am going to look into a clutch type LSD like a kaaz or a trd style

[Mirko]

No g is hilux there are 2 f series diffs. One from a targo that u have to cut down and the holy grail out of a Cressida where all you have to do is change mounts that's the one I have

[Mirko]

Also true trac are not harsh at all from what I read. The Kaza 1.5way in my s14 is harsh

[drift kid]

I have been told that the tru trac is harsh in that it is either locked or not, there is no inbetween smoothness as it is a gear type lsd not a gradual slipping of a clutch disc if you know what I mean, and kaaz probably aren't the best to reference off of, they are kinda noisy and rough but my trd lsd in my 86 is insanely smooth and I would love to get something similar to this for my ute

[Jip86]

A mate of mine has one in a xy and he loves it. Its very progressive on engagement/disengagement.

i cant comment on the noise of it tho, 406ci stroker makes the diff hard to hear.....

[Sam-Q]

A Truetrac as in a Torsen?

[Big T]

I have been told that the tru trac is harsh in that it is either locked or not, there is no inbetween smoothness as it is a gear type lsd not a gradual slipping of a clutch disc if you know what I mean, and kaaz probably aren't the best to reference off of, they are kinda noisy and rough but my trd lsd in my 86 is insanely smooth and I would love to get something similar to this for my ute

This is totally wrong. The notion of "locking" a torsen is not how it functions. It transfers torque to the wheel with the most grip and hence is working nearly all the time. This means it is smooth in transition.

[Skylar]

Also, note that if you get kaaz/cusco/TRD/whatever plate LSD for an IS200 (F-series), it will be much harsher than an equivalent AE86 diff. What I mean is that a IS200 is 230kgs heavier and is expected to have 235 or bigger tires on it so the pre-load is much higher than an AE86 diff which would be expected to run 850 to 1000kg or so and a 195 in most applications.

It won't be harsh in the way of clunk-clunk-clunk(kaaz is worse for this than the other two I mentioned) but it will 'lock' the wheels with the slightest force.

[Sam-Q]

It won't be harsh in the way of clunk-clunk-clunk(kaaz is worse for this than the other two I mentioned) but it will 'lock' the wheels with the slightest force.

With a torsen the weight of the vehicle and the friction off anything apart from the tires are all irrelevant. There is no pre-load and no optimisation for any car more than another. Torsen's work purely via worm gear principle or some kind of spiral shaped witchcraft as I can't for the life of me figure out how they function.

[Big T]

Sam this may help understanding the mysterious witchcraft.

http://m.youtube.com/watch?v=lZmsY2YvVsc

I run one of these and it is awesome. Mirko already knows my recommendation. Eoin up in qld who has Pete's old ae86 levin also runs an f series truetrac.

Edit: and the truetrac can also have preload built into them. The "open wheeler" test on oem torsens doesn't hold on trutracs. They will spin both in the same direction in the air due to the preload built into them.

[Sam-Q]

Nope, no video will overcome my ignorance! I have even had a 3D model which I can rotate to go "huh??". I should have another look at it again though.

I thought Torsen's usually spin both ways when off the ground? From what I have heard if one wheel has lost all grip then it will get all the power, but any drag on it is amplifified to the other side. This is why they are no good for when there is wheel lift. Also I have heard about people partially applyi and people use a "modified Torsen" which is what I assume you're talking about. I should of said I was talking OEM only.

Also I have heard about people partially applying the handbrake to multiple the resistance when slipping off road

[Skylar]

Sam, that last sentence is in relation to the rest of the post and still talks about mechanical plate LSDs, as most people relate harshness in LSDs to clunking.

[Mirko]

Yeah Eddie looks like I'll be ordering this week. Got donor diff now so getting there