My TII diff is shot and I don't have the money to rebuild it, so in the mean time I'm putting a welded n/a one in. I was wondering if anyone knew if I could just swap the end plates that the driveshaft bolts to or are they not interchangeable? If they are interchangeable is the TII driveshaft the right length or different? I'd like to keep from having to buy an n/a diff and ruining my TII diff to make one that will work if it's possible.
Thanks in advance for any help!

 

The pinion on the n/a and turbo diff is the same length, so the d/s would fit if the bolt pattern was right. The u-joints in the factory unit are "not suppose to be" serviceable, but I have heard of driveshaft shops doing it, and im sure one local to you could do the swap if you had the n/a pinion flange.

FYI the CV axles are not the same either also think about that.

 

I know they could make me a driveshaft I just don't want to do it cause they'd have to trash my TII driveshaft. I know the bolt pattern isn't right, that's why I need to know if the plate or whatever on the driveshaft that the diff bolts to can be swapped with the one for my turbo diff. That way I can just put that one on the na diff and be good to go. I'll prolly just end up dropping the diff tomorrow and going for it.

Thanks for the help man.

 

You would need to get the u-joints out to replace the flange for the pinion.

 

I don't think you get what I'm saying. At the front of the diff there is the round plate that the driveshaft bolts to. There is a big nut that holds it on. I am wondering if I can take that plate off and put the one on from my TII diff. I don't want to have to mess with the driveshaft at all.

 

cheap *** FC owners damn. just get a used s4 turbo diff. A lot of them still work after all these years as long as you don't go drifting or doing burnouts.

n/a diff will break. it's only a matter of time.

 

I seem to remember reading about someone that tried to swap pinions between NA and TII diffs like you're suggesting, but it didn't work. IIRC there was a small difference (length?) because one is meant to be used with an 8" ring gear, and the other is used with a 7".

You've got 2 options:
1) Buy a TII diff
2) Buy/pay someone to make a custom driveshaft

You're going to spend money with either option.

 

I already have a TII diff. It just never locks.

Arghx, the car is being built specifically for drifting. I also thought the n/a diff wouldn't handle it but I found out that Jeremy Lowe, who is first in Pro Ams right now, is running a welded n/a with custom halfshafts.

I need something predictable, not something that's going to open midway through a drift and send me into a wall.

Thanks for the info Rotary Rocket, you just saved me a lot of pointless work. At this point I think I'm going to tear my TII diff apart and see what it looks like. Either shim it or I heard you can just throw another clutch plate in it and it's basically like having a welded.