I recently bought a differential off a guy who claimed this to be a stock s14 open diff.
When I got it home and checked it out more I realized it wasn't, both outputs spin together instead of opposite directions so I'm guessing LSD or VLSD.
The problem is I really have no clue what it is or what it came out of, I've searched many sites which makes me believe it's from an R32/R33 Skyline, 300zx, or who knows what.

If you guys have any idea, that would be great, heres some info on it.

Gear ring says 49:12 final drive

Has sensor on it, for ABS?

Stamping on the casing is as follows:
Top- 38311
43610
Bottom- 0203109
KN23
47

Outputs also have a 3, 2 bolt pattern.
Input is 4 bolt.

Bottom:


Top:



Outputs:


Ring Gear:

Looking at it quickly, thats a ABS model VLSD S14 diff, off of top of my head it would require ABS driveshaft which are apparently shorter.

Give away,
ABS sensor up front
Large bushing mounts up front (S14) (s13 has small holes)

As for VLSD or open diff,
"VISCOUS LSD" orange sticker on cover, but u dont have cover probably, and their swapable between all diffs
When u spin one axle flange other side should spin same way,
If you spin driveshaft flange(pinion side) both axle flanges will spin same way.
With both axle flanges out if u look accross VLSD (LSD) vill have 0 shape all the way accross, gets narrow in middle off diff but u can see all the way accross
With axle flanges out and Open Diff, u cant see accross all you will see is spider gear cross.
******more technical********* and since y have cover off
VLSD is a clutch pack LSD- diff carrier will be enclosed holding clutch packs for both sides, has holes all the way around carrier spaced out.
Open diff is easy u will see spider gears and spider cross and big 2 holes, one on opposite side of carrier, u can tell because people weld their spider gears to cross or carrier housing to make it full locked, if yours looks like that than u have open diff.

P.S. as for the diff ratio thats a 4.08:1 ratio think thats stock for S14 or about, I run 3.50:1 or so on my S13 my VLSD is off of Q45 Infinity with hub bearing carriers and drive axle off of 300zx TT

Matt.