I am attempting the install of an OBX limited slip diff into an 1991 S1 manual tranny case. I have pressed and re-pressed the bearings. I have tried my original 1.4mm thrust washer and also a 1mm thrust washer. Both washers bind upon tightening.
I have just measured the diff/housing space using no thrust washer and tightening some of the case bolts to 15 ft/lbs. Just a test. My feeler gauge is tight at .021 in or .533mm.
There is supposed to be ~.010 clearance after tightening the tranny case. This means I need to find a thrust shim as skinny as .523mm??? HAHA. Skinniest S1 manual thrust shim is the 1mm at this size.
Oh, I have shaved the heat flanges in the clutch housing. Maybe I need to shave more? I do not think so. I blued the bottom of the clutch housing bearing seat and found it to be in contact with the bearing. The diff is seated.
What happens if I run without a thrust bearing?
Can I have a shop shave the tranny housing (passenger side) bearing seat????
Are there any S1 thrust shims as skinny as I need?
I'm thinking OBX limited slip is meant to run without a thrust shim.
Any ideas?

 

The OBX is poorly sized (yes, I have one). You will need to custom grind your shim if you want the clearance within spec.

 

i had to grind the original shim to make the proper clearance for the OBX diff also........not that big a deal.....take 5 minutes to do....

 

OK, thanks guys. Now I have to figure out how to grind this puppy evenly. Hmmmm. At least I don't feel like I've been tricked!!!!!!! haha.

 

I had to grind mine too. I was very very close to using a piston ring that I found that was perfect thickness.

 

OK, I grinded the 1mm shim to fit. Not perfect but functional. Tommorow I will re-assemble. UNtil the next adventure. Thanks to all.