F series diff question

[Wedged'86]

can someone just clarify this for me:
An F series diff fits into an AE86 (with some minor modification) and an Altezza LSD centre fits into said diff.
is this correct?

Thanks.

[gianttomato]

All with modification.

[TurboRA28]

Yeah I wouldn't call it 'minor modifications'. The F series diff is a great diff and good width for AE86, but you need to cut off mounts and use a jig to weld on new mounts for it.

Unsure about the altezza centre sorry.. But you can use supra/4runner lsd centres & gears.

[Norbie]

Yup, you'll probably find the TrueTrac is the best/cheapest option if you want an LSD in an F series diff. There is a TRD centre for the IS200/Altezza which fits but it costs a shitload more.

[WDE_BDY]

Hopefully in the next month of two I will confirm fitment of the Altezza centre, will post up once I do.

Callum

[gianttomato]

Altezza centre fits. You need a spacer ring to space out the crown wheel.

[Bahnugget]

TrueTrac? that some sort of 4wd locker?

[TurboRA28]

Torsen....

[Wedged'86]

Thanks,
I knew i'd have to use a jig to put change the mounts over from the sprinter's diff over to the F series.
But I was pretty sure (i was told by a reputable source) that the altezza centre would fit straight in.
what's involved in using a spacer ring? is it hard?

Thanks again.

[gianttomato]

The flange to which the crown wheel ius mounted is thinner. You need to make a spacer ring to effectively thicken this flange to the one found in a non Altezza centre so that the crown wheel and pinion will engage without the centre being pushed over a mile to one side by the adjusters.

Do it and you'll see what I mean. You'll need to get one made up at a machinist.

Look up posts by Pure_in_sanity - he put a Supra IRS LSD into a Hilux centre - same deal.

[1JZ-Rolla]

Altezza centre fits. You need a spacer ring to space out the crown wheel.

I didn't have this problem, crown wheel offset was the same as my MX13 Corona live axle centre, with the carrier bearings still being equally centred by the adjuster rings.

I know this doesn't show the correct angle detailing the flange offset, but for interest sake, this is a pic of the IS200 ("Altezza") Torsen hemisphere on the left, vs MA61 Supra 1 pinion clutch type LSD hemisphere on the right.




Cheers
Phil

[RT104GT]

I didn't have this problem, crown wheel offset was the same as my MX13 Corona live axle centre, with the carrier bearings still being equally centred by the adjuster rings.

I know this doesn't show the correct angle detailing the flange offset, but for interest sake, this is a pic of the IS200 ("Altezza") Torsen hemisphere on the left, vs MA61 Supra 1 pinion clutch type LSD hemisphere on the right.

Cheers
Phil

QUESTION is the photo on the right what I need to put into my CORONA F series to bring it back to LSD?

If so does the spline come as standard to fit the MX31 a.k.a. F series Corona 1973?



I have a second hand 3.909 Mark2 F series MX13 and also a 4.100 original Corona (1979) running in the car, both use the same fine spline (40+) so I have choice of two carrier assemblies that I can use to modify one and experiment with a clutched lsd centre. (If I can find the correct fit).

The Mark 2 MX13 axles are one inch 3cm longer than the Corona GT axles and cannot be machined down as there wont be enough spline left, so I can only use my original axles.


This is all I need to know besides where to buy one used or new thanks.

[gianttomato]

I didn't have this problem, crown wheel offset was the same as my MX13 Corona live axle centre, with the carrier bearings still being equally centred by the adjuster rings.

Interesting. The one I saw definately had a different flange offset.

[WDE_BDY]

If someone want to give me a pic of where to measure etc, I can get all the details on the Altezza one. It is still sitting in the box at the moment, hopefully will get time to pull the Crown diff head out to compare this weekend.

Callum

[Bahnugget]

sorry to hijack but a truetrac centre fits in a non-lsd F series housing with no modifications?