I'm slated to get my differential (just the unit itself, not the entire housing) replaced next month.

A bit of backstory: The car came with a far to aggressive aftermarket LSD in it that I'm not a fan of, so I'm going back to the OEM Torsen unit.

Now I know a Torsen unit isn't exactly "rebuild able" per se. However, I'm curious as to if there are any installation kits, etc that I can buy, what bearings I would need, etc. Again, all I'm having swapped over is the actual lsd unit itself. I've seen a bunch of shims, etc in the parts catalogue, so I'm not exactly sure what I'll need, and I don't want to buy parts if I'm not going to need them, unless my only option really is to buy every shim listed, etc.

Any insight would be much appreciated!

 

I've kinda/sorta done this when I upgraded to a RX-8 4.44 ring and pinion. You may want to look in threads on that upgrade since it's the same procedure.

If memory serves go ahead and get the outer seals. I know you also need the front nut and crush sleeve as well. I can't remember on the bearings, that thread should have that info.

If you can find a 4x4 shop they can do it for you no problem, 4x4 guys do stuff with setting up diffs ALL the time. It's a very straight forward differential, there's nothing super special or weird about it. Just print out the shop manual pages that have the torque specs and everything, that's all they would need. I think I had mine done for like $100 or something - brought the diff and all the parts and picked it up the next day.

Dale

 

I've sent multiple emails to quite a few shops and I've gotten no reply, which is the weird thing. I finally found a shop nearby that specializes in doing work for the local autocross club, but my appointment is a month away. I'll go ahead and touch base with him now that I think about it again, he said he was going to look for a differential install kit, but I don't think one of those exists for our cars.

 

Emailing a shop is as good as emailing your shoe. Either call or go by there. They are typically WAY too busy to deal with emails. This is especially true for small local shops.

Dale

 

Why not buy a used diff from a recycle yard. Check the backlash. If needed buy new spaces to adjust it.

When I went to an auto 3.909 diff to go with my JDM 7 series trans with the .806 fifth gear, it's backlash was loose enough to shift the ring gear over by the next size spacer and be in tolerance.
If your engine is stock, you might not want the taller 1-4 gears resulting from my my swap. In my case. having about 200 more wheel hp does not hurt acceleration.

 

I've already got an oem diff on the way, but I can't imagine finding a used rx7 diff out of a salvage yard, I wish parts were that easily available.Going to stick with the stock ring & pinion. I thought about the automatic one, but as the car is mostly stock at this point, I'll keep it as is for now, eventually, that will probably be the route I will take.

 

If going for more power think about getting them to build it with a solid pinion spacer instead of the crush tube.

Install a diff brace, new bushes and fuel filter while you are there.