jasono718

iTrader: (-1)

looking to upgrade my 90 miata rear differential.. sick of the one wheel spinning... can anyone recommend what differential will work best...1.5 way or 2 way?? mazdaspeed or kaaz or tomei?? anyone know which one is better for a swap??

Ike

Just do a torsen swap from a 94+. You'll need the drive shaft, pumpkin with meatball, and the CV axels.

jasono718

iTrader: (-1)

id rather go with all new parts insted of find all those parts..
how does that set up compare to a new diff??
thanks

jasono718

iTrader: (-1)

*instead

akaryrye

iTrader: (5)

the reason you want to do the 1.8 rear end swap is because its much stronger. In fact, somebody just broke their 1.6 rear end just yesterday. Of course he had more power, but if you are making your wheels spin regularly, I wouldnt expect it to last too long.

beerslurpy

1.8 torsen. All the other easy choices are based off the 1.8 torsen body. Im running GURU guts, but I only did that because I was running open diff guts before and it wasnt much more expensive than going to a mazda torsen.

magnamx-5

iTrader: (7)

yeah dude 1.6 diff is weaksauce.

akaryrye

iTrader: (5)

hey i havent seen beerslurpy around in awhile.

bripab007

Going with a brand-new Torsen over a used one won't be any stronger/better, really. There's nothing in a Torsen that really wears down significantly; it's all just gears...it either works or it doesn't.

Now the CV joints on the axles and u-joints on the driveshaft, on the other hand.

beerslurpy

I post regularly here.

akaryrye

iTrader: (5)

lol, your right, i guess i didnt notice. Maybe i remember your name from when i used to check out m.net and liked the name.

jasono718

iTrader: (-1)

will a 99 4.3 open work???

akaryrye

iTrader: (5)

yup it sure will, you would still be spinning one wheel though. However, you could upgrade it to an rx7 clutch type lsd later on.

TheBandit

iTrader: (8)

Beerslurpy, so did you just buy the unit from FM, or did you rebuild yours with the GURU components? If so, where did you source them from?
-Michael-

Braineack

iTrader: (62)

Torsens are so overpriced it's not even funny. You can buy new Kaaz or Cusco LSDs for the price people want for torsens.

1.8 Open rears are cheap, and even buying a used RX7 Clutch-LSD and rebuilding it will be a cheaper build than a torsen swap.

You can even find 86-88 RX7 assemblies with the LSD included. Use miata specific: half-shafts, ring and pinon, pinon housing (pumpkin), & diff mounts. And do a cheaper build.

jasono718

iTrader: (-1)

im thinking it would just be easier to buy the kazz lsd....
anyone agree or disagree?
getting all the other parts sounds like too much of a project..

Braineack

iTrader: (62)

If you buy a 1.8 rear with a torsen, just keep it as is (or sell the torsen for a good deal of $$$). Really decide what type of LSD you want.

Otherwise you have a few options. Buy a 1.8 open and swap in an LSD (RX7, kaaz, cusco, guru, torsen). or do a RX7 frankenstien coversion:


1.8 open converted to LSD:

Parts:
94-05 1.8 Miata open assembly
84-91 NON-TURBO Rx7 clutch-type lsd (or any LSD you pick)
94-95 Miata stub shafts and 94-95 Miata half-shafts
or 96-05 Miata axles (no stubs needed)
94-05 Miata driveshaft

Proceedure:
Open the 1.8 miata & pull the open diff. Bolt the ring gear to the LSD. Drop it in, set the backlash, and reassemble the housing. Swap/install as normal.


86-88 RX7 assembly conversion:

Parts:
86-88 RX7 NON-TURBO differential assembly
94-95 Miata stub shafts or RX7 stub shafts and 94-95 Miata half-shafts
or 96-05 Miata axles (no stubs needed)
RX7 Circlips (fit onto the end of the stubs/axles, miata clips will not fit)
94-05 Miata driveshaft
Miata or RX7 ring and pinon (ring teeth / pinon teeth = end-ratio)
Miata Pinon housing (pumpkin) (find at RX7 performance shops)
Miata Diff. Bushings

Proceedure:
Open the RX7 assembly. Decide what ring and pinon to use. Bolt the correct ring gear to the RX7 LSD. Swap the pinon gear and lsd guts to the miata pinon housing. Set the backlash, and assemble the miata pinon housing to the RX7 housing. Drill out the RX7 diff bushings and push in miata specfic bushings. Install as normal.

*note: the 85-85 LSD will fit, however, the housing is not compatable