Okay, from searching, ive noticed that everyone doing this swap is putting 1.8 miata lsds in their fcs.. Well what im doing is the opposite. my fc has a lsd in it, and my 00 miata has an open in it, and i want to put a welded in my fc for sliding. its not a dd, its a toy car just for sliding, so dont bust my bawls about replacing it for a welded.

But my question is, just take out the bare diffs themselfs and its a direct swap over..?? Im going to assume so, but i just want to make sure, since im apparently doing this backwards. also, is backlash something i can adjust by myself, or should i take it to a shop to do it?

 

Don't see why it wouldn't work the other way, just swap the ring gears as you would for the Miata torsen into FC NA pumpkin, except you are actually going to use the Miata's ring gear again, with the FC LSD.

I don't know about the backlash setting - I've looked up how to do it, because I'd like to do the Miata torsen swap, and I remember thinking I should probably just get someone who knows better/has the right tools to do it.

 

okay well due to it being cheaper, i am just going to trade my diff for an open (+ cash of course) or sell it and buy an open..

which leads me to this question.. if i switch to open, can i reuse my LSD output shafts or do i have to get open output shafts? with a miata, the shafts are specifically for open and lsd, im looking into the answer right now, but still havent found it. thanks.

 

if your LSD is a viscus type from an 89-91 car it has unequal length output shafts. Thus you will need to source equal length output shafts from an open diff (any year FC) or 86-88 clutch type LSD.

Are you trading with another RX-7 or with a miata?

 

I would have a performance shop do it for you. you can easily brake gears if you set the back lash wrong.

when I swapped a FD torsen into an Turbo FC carrier I paid a friend of mine who is a performance shop mechanic $100 to do it.

 

i have an 88 fc and an 00 nb miata...
but im pretty sure the guy before me put it in, since see my miata is a DD so i really really dont need an LSD in it. So im thinking about selling my lsd and just buying an open, or trading it to someone with monies on top. So its like i could pay someone 200 bucks to set both of the backlashes, or i could make a little money off of it and not have an LSD for my miata, which doesnt really need it anyways.