Fb lsd?
 

Can anyone please point me where I may find and LSD from my FB? Not for racing but spirited street use. Any advice would be greatly appreciated.
Thanks.

Hang on...you can swap it for a miata diff with a torsen???

GSLs had LSD in em OEM, so if you can find one of those from a junkyard, your good to go.
May want to rebuild the LSD before plunking it in there.

Hi t_g_farrell.

No scrap yards in Manila sad to say. Also Mazda never sold any rx7s over here.
I read somewhere that a miata torsen will fit into the diff of an early FB. Anyone here done that?

Only the 7" miata diff since the rx7 differential is 7". Dont get the smaller one. Also i think it will only accept the 84/85 axle siince those years have larger spline and bigger bearings.

I thought I replied with my thanks to Whizbang already but I don't see it.

Trying again.

Thanks Whizbang!!!

did you try google?

ok so
gsl's have 3.90 lsd, but after 1983.5, they became large axle through end of production year ('85)
gslse (84/85) have a 4.11 lsd, big axle of course
Yes Miata pumpkins can be swapped in

so can, mazda 80's truck front diff's which are 4.44

So can kia sportage (90's) front diffs, which are 4.77

you can also source custom lsd's, like I just picked up an '81 GSL rear with 4.88 gears in it

Just bear in mind your axle to what pumpkin you're putting in it, OR if you swap the whole rear to acquire disc's, that's fine but you also have to swap out the proportional valve up by the master cyl AND WHAT MOST PEOPLE FORGET ABOUT is you'll need different E brake cables for the disc rear

So if you find a LSD/Disc rear at the junk yard, make sure you get
1) complete rear with calipers
2) take the proportional valve from the engine bay
3) get those e brake cables

probably more than you were looking for but hopefully the next person searching will find this thread and the above info and it'll solve duplicate posts down the road :)