OK here is the list of internal parts and my measurements.

First I labeled the consumable parts, those consisted of 4 fiber coated disks (#6) and 8 metal disks with external splines (#5 and #4). #4 is the cup spring which is NLA and replaced with the newer style belleville washer 928.332.555.20.

Additionally there are 2 differential shafts (#11) with 4 spider gears (#10) with 2 thrust rings (#7) and 2 bevel shaft gears (#8) with 2 treaded pieces (#9) and 2 circlips (not seen in this diagram), these make up the center of the diff. These items with the cover (#2), LSD body (#12) and 2 thrust washers (#3) complete the unit. Additionally #1 in this diagram is the cover attachment screws (NLA) for the 914 part, substitute the 65-89 911 pan head screw part 900.119.002.00, they are yellow colored not black, so don't let the concourse guys look into your 901 box!

Click to view attachmentSo 32 parts total make up this fascinating little gizmo!

I decided to make my measurements in SAE and metric.

Measurements of used parts

Outer spline A .0789 - 2.00 mm

Outer spline B .0785 - 1.99 mm

Outer spline C .0785 - 1.99 mm

Outer spline D .0780 - 1.98 mm

Outer spline E .0784 - 1.98 mm

Outer spline F .0785 - 1.99 mm

Outer spline G .0790 - 2.00 mm

Outer spline H .0795 - 2.02 mm

Fiber disk A .0765 - 1.94 mm

Fiber disk B .0750 - 1.91 mm

Fiber disk C .0775 - 1.96 mm

Fiber disk D .0775 - 1.96 mm

From here I will use SAE measurements, I will introduce metric measurements for illustration.

Than I set about measuring the body, cover and the thrust ring stack

Body internal 3.884 and the cover is .2440, the cover needs to be subtracted from the body because it fits inside so 3.640.

When assembled the thrust ring stack measures 2.682.

So we take inside of the LSD 3.640 and subtract the thrust ring stack 2.682 this leaves us with .958 space for the consumable parts.

There is a total of 12 disks, each group of 6 needs to take up .4790 or 12.17 mm

So there we have the used parts, next post I will measure the new parts.

Mike