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Re: Building an RX7 LSD diff
Posted: Sat Jan 04, 2014 7:42 am
by DB RX63
I think a 4.7 CWP would be a bit too wild for street use really.
Re: Building an RX7 LSD diff
Posted: Sat Jan 04, 2014 10:09 am
by TOOL
My thoughts too but I wanted to hear it from someone else too
Re: Building an RX7 LSD diff
Posted: Mon Jan 13, 2014 10:49 pm
by TOOL
I did a demonstration of the backlash check and bearing preload checks to the new owner of the S3 Torsen LSD. No photos, but happy to say it was incredibly close for a base setting (and probably would have been fine) but decreased the backlash 0.04mm and checked and reset the bearing preload to within 0.03mm of target.
Even better settings than the factory untouched open diffs had for comparison.
I hope you're happy with it bud.
Re: Building an RX7 LSD diff
Posted: Mon Jan 27, 2014 8:30 pm
by TOOL
Hi guys,
I thought I would show you a few pics of the FB clutch type LSD.
After removing the diff centre from the carrier, take the centre and remove the 4 screws keeping the top on the casing.
Here is the inside of the top. The inner ring is where the thrust washer sits. The next ring is where the cone spring sits.
Here you can see the copper thrust washer and cone spring in situ.
And this is what they look like.
Here you can see one of the clutch plates from the stack, with the splined side gear. These side gears were used in all 10A and 12A powered rotary cars up to 1983 and are very hard to find now.
This is the clutch stack
And this is the surface for the inner clutch stack.
Here’s the spider gears.
And the main LSD casing.
Check and inspect. Replace as required and reassemble. It should look like this again.

Re: Building an RX7 LSD diff
Posted: Mon Jan 27, 2014 9:04 pm
by KiwiDave
That's a nice carpeted workshop dude.

Re: Building an RX7 LSD diff
Posted: Tue Jan 28, 2014 10:26 am
by TOOL
Far too cold in the garage at the moment, even for me lol.
Bottom of the stairs it is.
Re: Building an RX7 LSD diff
Posted: Sat Feb 01, 2014 3:40 pm
by TOOL
2x LSD centres sold today.
I can get try and locate more if there's interest.
PM or post here.
Re: Building an RX7 LSD diff
Posted: Mon Mar 10, 2014 9:42 pm
by JayoM
Awesome thread! A lot of useful information for sure, and clears up alot of 'claims' you see on the net. Good stuff

Re: Building an RX7 LSD diff
Posted: Mon Mar 24, 2014 8:21 am
by rivalrx
Cracking thread Tool. Thanks for taking the time to document and share!
Re: Building an RX7 LSD diff
Posted: Mon Jan 12, 2015 7:29 pm
by Lucky
MR TOOL, can you offer any advice as to which flavour of MX-5 diff will fit in this process? I might be able to get hold of a Torsen diff from a top-spec Series 2 MX-5, will that be OK? I'm guessing a Torsen diff is preferable to a multi-plate one