Torsen differential

JP147 · Post by **JP147** » Sun Jun 28, 2015 7:26 pm

Sorry if dumb question, but what is stopping me from just sticking a torsen diff in my MY wagon? I see there are R160 torsen diff centres available.

Phizinza · Post by **Phizinza** » Sun Jun 28, 2015 10:32 pm

Aren't those only in female type stubs?

JP147 · Post by **JP147** » Mon Jun 29, 2015 10:46 am

That doesn't seem like a bad thing since the normal male stubs seem to break easily. But would I need to use a different housing as well? I am quite interested in getting either a locker or a Torsen.

Phizinza · Post by **Phizinza** » Mon Jun 29, 2015 6:36 pm

Whats the plan to get MY rear shafts to mate to the female diff stub type?

JP147 · Post by **JP147** » Mon Jun 29, 2015 7:28 pm

The first thing that comes to mind would be to get shafts that fit the diff, take the outer joints off, get the spline cut to match the MY outer joints and put them on.
Uni joints instead of CVs would be ideal but I don't know if that is a realistic idea.

People use r180 3.90 torsen diffs in Datsuns with custom shafts, so with a little money it seems like it could work.

JP147 · Post by **JP147** » Mon Jun 29, 2015 8:28 pm

Now that I think about it, an r180 locker would be better. I just have to work out what things I need to make it fit.

YouTube · Post by **El_Freddo** » Mon Jun 29, 2015 8:37 pm

The real trick would be to find an r180 locker. ARB list the but AFAIK they don't actually make them anymore

Otherwise I'd probably have one in the back of Ruby Scoo already

With your adaption of the drive shafts to the female diff you might get away with putting a circlip on the male stubs to hold them in the diff. This will only work if they're the same spline type as the matching drive shafts to the diff (clear as mud?).

Cheers

Bennie

JP147 · Post by **JP147** » Mon Jun 29, 2015 8:53 pm

It would be good if the splines are the same, I will cross that bridge when I come to it.

So the main hurdle is finding an r180 locker? Would I have better luck finding an air locker than an auto locker? Either one would do for me. An air locker would be pretty cool actually.

And if I do find one, would I need a Nissan housing to put it in or would it fit in a Subaru one?

YouTube · Post by **El_Freddo** » Mon Jun 29, 2015 9:01 pm

Subaru/Nissan, the cases are pretty much the same since they're using the same design.

Diff stubs on the R180 I'm 99% sure will not fit directly.

Cheers

Bennie

JP147 · Post by **JP147** » Mon Jun 29, 2015 9:35 pm

Ok, seems like I need to either find a r180 or r200 locker, and then get a corresponding diff with 3.90 gears. Then get driveshafts that fit or have some made. I will need a custom tailshaft anyway since I would be doing a 5 speed swap as well. Am I missing anything? Any major problems with this idea?

YouTube · Post by **El_Freddo** » Mon Jun 29, 2015 9:39 pm

None that I can think of but I'll be keen to see how you go with this!

I hope you get something sorted so I can copy it if you go the way I want to with mine

Cheers

Bennie

JP147 · Post by **JP147** » Mon Jun 29, 2015 10:05 pm

Sounds good.

It might be a while since I need to get my Datsun going before I can take the Subaru off the road and I want to get all the bits I need first.

Also I don't really know what I am doing but I won't let that stop me.

AndrewT · Post by **AndrewT** » Tue Jun 30, 2015 12:43 am

I have been as far as getting a nissan irs R200 diff on the workbench at ARB and looking at an ARB air locking centre with the ARB mechanics. It doesn't work. The input splines work, but the stub axels have no chance of working, the circlip setups are all wrong. Would need completely custom stub axels machined up from scratch. The ARB air lockers for R180 and R200 are meant for live-axel diffs so you'd be looking at trying to change your whole rear end to live axel, customising tailshaft, and hopefully getting a rear diff ratio suitable for your Suby gearbox.
That being said, after some further R&D I think I might have a winning recipe for getting an air locker into a Suby with only "moderate" retro-fitting / fabricaton but give me a while longer - I've wasted a bit of cash on the R&D already and wouldn't want others to waste more if it doesn't work heh.

YouTube · Post by **El_Freddo** » Tue Jun 30, 2015 2:08 am

That's where the issue will be andyT, did you try a set of front diff stubs? These are larger than the r160 rear units.

I've got some R&D going into a hilux ifs diff. I *should* be able to get my required 4.111:1 ratio but first I need to fit it into the back of the subi and work out the output stub situation.
One other problem is the sheer weight of this diff unit - probably about two r160's put together!! Would definitely want to beef up rear suspension after that...

I'm not sure where I'll go with it yet, got a few other things to sort out first - like a gearbox!

Cheers

Bennie

Silverbullet · Post by **Silverbullet** » Tue Jun 30, 2015 3:31 am

JP147 wrote: Any major problems with this idea?

Maybe not in theory, but it'll probably be a lot harder to do than you think

JP147 · Post by **JP147** » Tue Jun 30, 2015 10:38 am

Aren't these lockers used in IFS front diffs?

AndrewT · Post by **AndrewT** » Tue Jun 30, 2015 12:48 pm

Kindof. The Nissan ones (which suit ARB Air lockers) are mostly like this I believe:
http://www.4x4parts.com/images/F118372536.jpg
I think the retro-fit would be a bit extreme to get this going in the rear of a Suby.

I have the parts and plan I need to make this work (I think):
- Late model IFS rear diff (basically the same "shape" as a Suby rear diff, just quite alot bigger, which has an off-the-shelf ARB air locker still stocked and produced.
- Rear diff is in a ratio which suits my Forester gearbox (4.111 - the only ratio available for this diff which suits any Suby gearbox).
- A solution worked out for the two rear axels which will definitely work (apparently).

All I need to do is:
- Mess around with the mountings and fabricate some brackets to actually mount the diff to the car (should be quite easy in my L series).
- Get the rear end of my tailshaft lengthened slightly and the coupler changed to suit this diff.
- Custom modify the rear axels to suit.
- Once it's proven to work in the car, actually buy the air locking diff centre.

I'm comfortable running a modified tailshaft. Tailshafts last for ages and everyone runs modified ones for AWD conversions in L series anyway. With new unis it's bound to last longer than a crusty old unmodified one.

I'm comfortable running custom diff mount brackets. It's the kindof thing that if done right, is pretty much a "set and forget" mod.

Modified rear axels I am not quite as comfortable with as axels can have various issues offroad and are fairly essential for the car to still drive. I guess if I have a locking centre diff I would still be able to drive, but it would still be nice to be able to just buy a replacement axel off the shelf - can't do that with custom modified ones. However, I can always have a third one modified to keep as a ready-to-go spare.

One other thing is this diff is so damn big that it is likely to hang down nearly 3" further than a Suby R160. I plan to counteract this by mounting it right up in the almost original position (right up close to the fuel tank). In other words, NOT drop it 3" with my 3" body lift kit like you normally would. Won't this kill my CV joints? I am hoping this isn't an issue. The outputs from the diff are quite low, and the way these custom axels will work out I think they will comfortably soak up a bit more angle.

I will get on with this hopefully in a few months' time. I spent quite a bit of time on this but made the decision to shelve it for the moment and concentrate on getting my car to actually drive first!

Phizinza · Post by **Phizinza** » Tue Jun 30, 2015 7:30 pm

I seem to remember Datsun Hitachi R diffs use bolt on style CVs like the Nissan's do

JP147 · Post by **JP147** » Tue Jun 30, 2015 8:54 pm

Sounds like a good plan. It will be good to see the axles you get made.

If it all works out, I will then need to find a way to do it with 3.90 gears. There must be stubs that fit an IRS diff and will also fit a locker.

When you say the input splines work but the stub axels have no chance of working, do you mean they fit in but the circlip is in the wrong spot?