Will a Torsen LSD out of a FD3S fit an FC3S? If it will fit, where can I obtain 4.30 gearing for it?

I know for a fact that the stub axles (diff side of the half shafts) for an FC fit in the typeII torsen out of a Miata.

What I do not know is if the torsen bolts right into the rx7 diff housing... but I bet you a shiney new nickel that it does.

I can't say about the FD torsen.

Good luck

I hear FD torsen fits t2 diffs, while miata torsen fits NA diffs.

I've also heard a lot of the higher power FD people use TII diffs as the FD torsens are weaker.

Maybe I should rephrase my question. What is the best (most inexpensive) way to put a LSD into my GTU w/ 4.30 gears? Finding a GTUs rear is pretty unlikely. Miata LSD? FD LSD? GXL LSD? HELP!!!!

i HAD a GTUs... they are rare just gotta keep looking https://www.nopistons.com/forums/pub...DIR#>/wink.png

Which of the others will fit?

well the gears you can buy.

any diff from an 84-92 non turbo, or a 94+ miata will fit, the 84-88 diffs are clutch type, the 89-90 gtus diff is viscous, and the 94+ miata is torsen.



mike

I hear clutch type (s4) diffs are better for things like drag racing. The cheapest way is probably to find a GXL and get the diff. The 4.3 gears don't make that much difference, so I wouldn't bother with them.

4.30's made a huge difference in my vert, night and day difference

GXL diff is different than a t2 diff i believe.

I have an extra torsen I coulkd sell you. Asking $300 obo

yeah, the TII diff won't bolt to the n/a driveshaft without modifications.

Apex13b, you also went from a 3.9 to a 4.3, and that's a big difference. 4.1 to 4.3 is much less of a difference.

I beleive all S5 verts were 4.1 final drive, regardless of auto or manual. The 88 vert had the 3.909 final drive ratio.