Building an RX7 LSD diff

Technical info not specifically 1st gen RX7 related.
biznatch
Posts: 330
Joined: Mon Aug 26, 2013 3:03 pm
Location: Hornchurch, Essex

Re: Building an RX7 LSD diff

Post by biznatch » Wed Jan 14, 2015 6:32 pm

Thanks for clarifying. T2 added to my 'summer' job list :D

Lucky
Posts: 2686
Joined: Mon Nov 07, 2011 8:30 pm
Location: Worthing, UK

Re: Building an RX7 LSD diff

Post by Lucky » Wed Jan 14, 2015 9:58 pm

re japi wrote:Lucky, I have diff for sale. Just started a topic in sales section. Also, its for sale in Facebook rx7fb site...
Thanks for the heads-up, but I'm guessing postage from Finland would he horrific :shock:

re japi
Posts: 198
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Location: Finland

Re: Building an RX7 LSD diff

Post by re japi » Thu Jan 15, 2015 3:25 am

Its about 85-90£ shipped to UK :)

TOOL
Posts: 2509
Joined: Thu Sep 01, 2011 10:30 am
Location: Var, France (ex NZ, ex UK)

Re: Building an RX7 LSD diff

Post by TOOL » Sun Jan 18, 2015 9:04 pm

Here's a 24 spline LSD I'll be putting together (just doing some cursory checks)

Image

Image

Along with a set of 4.44 gears

And this is why I like the clutch type Mazda LSDs, Mazda still sells new parts for them

Image

Crush tubes for the pinion and oversized thrust washers for the clutch stack (better lock up) :D
Back in sunny France

mc turbo

Re: Building an RX7 LSD diff

Post by mc turbo » Mon Jan 19, 2015 4:54 am

Lucky wrote: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
hi nik apparently there is a better lsd than the torsen lsd called automatic torque biasing lsd ATB, made by Ashcroft transmission which uses helical gears & @ £220 new with warranty it looks like its good value for the money!

User Banned

Re: Building an RX7 LSD diff

Post by User Banned » Mon Jan 19, 2015 5:50 am

Anyone looked into whether there is an Eaton Trutrac (torsen) centre for us? They seem good value too.

TOOL
Posts: 2509
Joined: Thu Sep 01, 2011 10:30 am
Location: Var, France (ex NZ, ex UK)

Re: Building an RX7 LSD diff

Post by TOOL » Mon Jan 19, 2015 8:16 am

mc turbo wrote:
Lucky wrote: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
hi nik apparently there is a better lsd than the torsen lsd called automatic torque biasing lsd ATB, made by Ashcroft transmission which uses helical gears & @ £220 new with warranty it looks like its good value for the money!
Ashcroft Transmissions?

"We are a UK based company solely specialising in the supply of rebuilt manual and automatic gearboxes, transfer cases and differentials to suit Land Rover, Range Rover, Discovery and Freelander 4x4 vehicles."
Back in sunny France

mc turbo

Re: Building an RX7 LSD diff

Post by mc turbo » Mon Jan 19, 2015 5:14 pm

TOOL wrote:
mc turbo wrote:
Lucky wrote: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
hi nik apparently there is a better lsd than the torsen lsd called automatic torque biasing lsd ATB, made by Ashcroft transmission which uses helical gears & @ £220 new with warranty it looks like its good value for the money!
Ashcroft Transmissions?

"We are a UK based company solely specialising in the supply of rebuilt manual and automatic gearboxes, transfer cases and differentials to suit Land Rover, Range Rover, Discovery and Freelander 4x4 vehicles."
tool so whats ur opinion of this ATB diff vs torsen lsd?

TOOL
Posts: 2509
Joined: Thu Sep 01, 2011 10:30 am
Location: Var, France (ex NZ, ex UK)

Re: Building an RX7 LSD diff

Post by TOOL » Mon Jan 19, 2015 6:26 pm

An ATB LSD is a type of Torsen diff. I think the original Torsen patent expired and then it's been copied over and over. Gleasman designed it.

Here's a Torsen LSD for MX5 at £615 plus VAT: http://shop.quaife.co.uk/catalogsearch/ ... del=416&q=

Kaaz LSD is $1000.
Here's a light hearted read for you about KAAZ LSDs: http://magnusmotorsports.com/tech-artic ... erentials/

Viscous are junk. OBX seem to be slated too.

I'm not sure what you're getting for £220 new. You've still got to add side bearings and assembly. They can't be any good at that price.

The clutch type is the original Mazdaspeed design. It's what they put in the JDM 12AT. It's what they put in the GSL-SE. You can rebuild them.
I think they went with the Torsen later on cos they don't need maintenance.
The ones I get and build have all been in great shape. They're easy to work with, so I use them. I'm happy to install Torsen's if that's what people want. I did it to show it could be done.

Bottom line, they are both a huge improvement over an open diff. They'll both take 250hp all day too.
Back in sunny France

TOOL
Posts: 2509
Joined: Thu Sep 01, 2011 10:30 am
Location: Var, France (ex NZ, ex UK)

Re: Building an RX7 LSD diff

Post by TOOL » Mon Jan 19, 2015 6:32 pm

Here's a link to how to install an LSD centre if anyone else wants to do it themselves g-l

http://vintage.mitchell1.com/PClubData/ ... 747057.pdf
Back in sunny France

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