Mazda Clutch LSD to fit NB

paulie · Postby **paulie** » Thu Nov 01, 2018 4:18 pm

Hi All,

I have an old mazda clutch LSD that I am putting into a NB8A rally car. I have replaced any worn plates and it is good to go.

I have sourced the correct 26 spline side gears, but they came from a solid axle rear end and don't have any c-clip grooves.
It also looks like the half shafts will hit the metal pieces that hold the spider gears before it is fully inserted.

My current plan is to grind about 3-4mm off the end of the half shafts, machine a groove into the end of the side gears for the clip, then see what happens.

I was wondering if anyone had already tried this, and if they had any advice?

Some pics:
Side gear with half shaft inserted, You can see the top of the c-clip groove in the half shaft

20181101_160755.jpg

inserted into LSD, you can see it touches the centre, and there isn't much room.

20181101_160725.jpg

Cheers

Paulie.

hks_kansei · Postby **hks_kansei** » Thu Nov 01, 2018 4:36 pm

It's not really a common swap, since most people wanting a clutch pack rear end just source a centre from an RX7, or a TX3/Familia rear diff.
Or just buy a new one from Cusco/Kaaz/etc

I'm not super familiar with the clutch pack diffs, since i've only really had Torsens open to check inside.

So far as the side gears, cant see why there'd be an issue with machining a land for the circlip to pop into. Just make sure it's got a similar taper to the factory ones so that you can actually remove the shafts without having to shatter them.

Just curious, I assume the side gears are LSD specific?
And since they're from a live axle, I assume they're either an early RX, or possibly a B series (cant remember if they had an LSD option)

flycasta · Postby **flycasta** » Thu Nov 01, 2018 6:56 pm

The problem you have is that you have an old shallow ramp angle lsd and they were from the earlier 70s RXs and they wont allow the fitment of the stub axles. I have the steeper ramp angle parts and side gears with the circlip grooves if you want to fit those or send it/drop itboff to me and I can do it. You cant use mixing parts you have to use the correct parts for it to work properly. Otherwise sell it and but a cusco etc.