I've got two spare sc diffs laying around and a friend that works at a machine shop. So basically all you need is a mk3 LSD, axles and custom spacers for the bearings to fit a sc pumpkin? Might give it a shot and see what my buddy can come up with.
Soo I just spent a lot of hours of going from six speed 350Z trans swap over to Halon's build thread to where you chimed in on the MK3 diff swap, and I'm actually curious to know if you got anymore headway on this little side project.
From my understanding the MK3 diff will fit up into the subframe but the mounting will have to be sorted out and the extra length in axles can be accomplished by swapping the MK3 axles in place of the sc units. Lastly, the differential's driveshaft flange can be swapped for the sc's 3 bolt flange.
If this is all true then looks like I'm going searching and heck weld in mounting points to the subframe myself.
FYI, the mkiii diff is pretty weak compared to the sc diff, and of course it is much weaker than a tt 6 speed diff. The main problem is that the clutch system is under engineered. You can reshim them and add more spring tension, but the clutches will still fail pretty quickly if you launch on slicks or do any heavy drifting. Just spend the money on a diff that will last instead of hacking a weaker diff into a chassis it was never meant for.
You can make them last a while with upgraded parts, but it will never last as long as a trd lsd in an sc housing. Spend the money once and bolt in a reliable solution; or fab, and hack, and rebuild, and still be left with a weaker and very slightly cheaper alternative. I'm all for some diy back yard engineering if it will actually pay off, but after the labor, custom fabbing and the marginal end product, I'll take a trd diff in an sc housing every time.
welded diff have been shown strong in many applications. but not destroying tires on the dailly drive is what kills me, to be able to rock an lsd or even the (91-2) torson would be way to cool. alll the nissan guys get to swat around diffs from car to car, gonna hit junk yard and start one of these.... sooo, mk3 diff in sc casing, swap DS flang, and rock the mk3's axels.... and good to go rights..? or keep the mk3 pumpkin..?
Let me cover a few points on this differential issue.
I just finished a one year torture test of the TRD Clutch Type 2-way LSD in my SC. Got it for reasonable money.
It performed very well in the areas I needed being a New England, Year-round RWD Sports car.
Traction, lockup time, breakaway release, were all top notch as far as needing both wheels when you're ascending an ice covered 45* incline, in a blizzard with feet of snow coming down.
In Icy conditions where I had Studded snows on 8.5" wide Stealth TT Wheels, again the diff operated very well on acceleration, but on Deceleration, one can definitely feel the cars desire to under-steer off the throttle.
Driving the car like an A-hole fixes the under-steer, but sometimes, especially when you are in your 30's and have gotten in enough trouble over the years you just want to drive in a straight line.
The TRD 2-Way says, "No. You go sideways now!" and that can be a handful if you are a skiddish driver (Fortunately, us New England drivers are some of the bset in the world under these conditions) or if your power steering is a little heavy with that leak you haven't fixed yet.
So for DD how do I feel about Welded or aggressive 2-ways like the TRD?
I've Had both, and under a 4-seasons, gotta be like the USPS, through sleet and snow kinda situation?
Open Diff= 3/10
Welded= 5/10 (This can be scary with all seasons in the rain and snow if you don't have confidence)
TRD 2-way Stock 70% Acc/ 70% Decel rate=8/10 (Because of the traction, same applies as the welded diff)
Anyways, after all the blabbing I'm not a drifter, so I'm going for a 1.5 way locking action.
Which is why after my hiatus, I will continue the MKIII LSD Quest.
I also have some other things in the works like 4130 Front lower control arms but that's another can of worms!
Looking at both possibilities of MKIII LSD application, I'll report back soon.