Building an RX7 LSD diff
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Re: Building an RX7 LSD diff
I think a 4.7 CWP would be a bit too wild for street use really.
Met Blue Series 2 Elford Turbo
S3 Rally Car (Done - Motorsport UK Passport issued !)
S3 Rally Car (Done - Motorsport UK Passport issued !)
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Re: Building an RX7 LSD diff
My thoughts too but I wanted to hear it from someone else too
Back in the UK for the summer, maybe longer......
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Re: Building an RX7 LSD diff
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.
Even better settings than the factory untouched open diffs had for comparison.
I hope you're happy with it bud.
Back in the UK for the summer, maybe longer......
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Re: Building an RX7 LSD diff
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.

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.

Back in the UK for the summer, maybe longer......
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Re: Building an RX7 LSD diff
Far too cold in the garage at the moment, even for me lol.
Bottom of the stairs it is.
Bottom of the stairs it is.
Back in the UK for the summer, maybe longer......
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Re: Building an RX7 LSD diff
2x LSD centres sold today.
I can get try and locate more if there's interest.
PM or post here.
I can get try and locate more if there's interest.
PM or post here.
Back in the UK for the summer, maybe longer......
Re: Building an RX7 LSD diff
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
Cracking thread Tool. Thanks for taking the time to document and share!
@rotarymazda for random cool Mazda shiz on Twitter.
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Re: Building an RX7 LSD diff
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