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Pop quiz on the FC rear end

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Old 05-22-09, 07:52 AM
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the EMULSIFIER

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Question Pop quiz on the FC rear end

Put your fc skills and knowledge to the test and see if you can figure out what's goin on here (because I sure as hell can't)

This is the situation:
1. The car has a turbo motor + TII transmission swapped into it.
2. The transmission has a TII driveshaft attached to it, that also connects to the rear diff.
3. The rear diff is of unknown origin, but has the little white tag on the filler plug.
4. The halfshafts that are connected to the diff are 1990 GXL NA shafts.
5. Everything fits

How is that possible?
Im guessing the diff must be a TII LSD, as it mates to the TII driveshaft. But how is it that the NA half shafts will bolt up to the diff? I thought they were a different bolt pattern!
Old 05-22-09, 07:59 AM
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FL

T2 differential will have 11 cooling fins and an N/A will have 9.
Old 05-22-09, 08:32 AM
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The NA I took off the car has 8.
The diff on the car has 9.
I think there are more diffs than just the 11 fin and 9 fin

If what you're saying is true, how is the TII shaft mating up with the diff if it's NA.
Old 05-22-09, 08:34 AM
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You have an aftermarket driveshaft.
Old 05-22-09, 08:40 AM
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First pic is the NA diff taken off the car

Second pic is the mystery diff.

Note the 8 ribs on first, 9 on second.
Attached Thumbnails Pop quiz on the FC rear end-dsc00091%5B1%5D.jpg   Pop quiz on the FC rear end-dsc00092%5B1%5D.jpg  
Old 05-22-09, 08:43 AM
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Originally Posted by LargeOrangeFont
You have an aftermarket driveshaft.
Do i? It sure looks like a 20 year old TII driveshaft
Old 05-22-09, 04:35 PM
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Originally Posted by flipstar
Do i? It sure looks like a 20 year old TII driveshaft
There is no magic going on here. You have an NA rear end and axles. You have a TII engine and tranny.

Therefore you have a TII driveshaft with an NA flange. Such a driveshaft is custom made, or aftermarket.
Old 05-22-09, 05:48 PM
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LargeOrange- yeah, you're right. The pic on the right is an s4 GXL viscous-type LSD, and the driveshaft must be custom.

You are winner ha ha ha!
Old 05-23-09, 02:38 PM
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dosen't mazdatrix sell a adapter driveshaft similar to that? for T2 To Na Rear end
Old 05-23-09, 03:09 PM
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Originally Posted by AmviciousRav
dosen't mazdatrix sell a adapter driveshaft similar to that? for T2 To Na Rear end
Yes they do, and supposidy the automatic driveshaft bolts up in this situation as well but don't support as much power.
Old 05-23-09, 06:15 PM
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i kind of just ran into this problem, being told the diff was from a turbo to find out it was just a na lsd when i went to bolt up the driveshaft and it was a no go
Old 05-23-09, 06:21 PM
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just take a die grinder to the holes and elongate them a little and the TII driveshaft will mate to a N/A rear every time and is cheaper.
Old 05-23-09, 06:24 PM
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the automatic driveshaft dosnt actually work. it does bolt to the NA diff, and the shaft does fit the TII tranny. but its 2 inchs shorter because the auto tranny is longer... so really it would just dangle between the two.
Old 05-23-09, 06:25 PM
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Originally Posted by jfpimp91elkland
just take a die grinder to the holes and elongate them a little and the TII driveshaft will mate to a N/A rear every time and is cheaper.

wouldnt that make it weak and likely to brake or throw it off balance
Old 05-23-09, 06:28 PM
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Originally Posted by rx-711
wouldnt that make it weak and likely to brake or throw it off balance
yes. do not do this. and remember, once you grind it off. it can not be put back...
Old 05-23-09, 06:38 PM
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has anybody done this and had it work, id sacrifice a turbo driveshaft over $300 + for a mazatrix shaft but only if it wasnt dangerous
Old 05-23-09, 06:52 PM
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that would be a NA automatic driveshaft into a s4 na LSD unit

i *do* have a S5 T2 rear, S5 T2 halfshafts, and a S5 T2 Driveshaft for sale that I coudl ship to your door. PM me if you are interested.
Old 05-24-09, 12:33 AM
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Originally Posted by rx-711
has anybody done this and had it work, id sacrifice a turbo driveshaft over $300 + for a mazatrix shaft but only if it wasnt dangerous
No but I had my na auto drive shaft extended so it could mate with my TII Tranny.
Old 05-24-09, 10:45 AM
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Originally Posted by sen2two
yes. do not do this. and remember, once you grind it off. it can not be put back...
The amount being taken off is very minimal and its still a lot stronger than an automatic driveshaft. I got the idea from hypertek and there are many others here that have done this too without any negative results
Old 05-24-09, 11:55 AM
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I take mine to the drag track and the roadcourse all the time! No Problems! (slotted TII shaft to NA rear!)
Old 05-24-09, 12:46 PM
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I've seen the driveshaft getting slotted several times. As long as you have someone even moderately skilled at cutting and they measure out their work, their should be no problem.
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