Maybe we can get falcon to elaborate on a comparison between the M1 and OBX.

Hmmm - Okay. :)

I will admit that my understanding of the TorSen is pretty rudimentary - While the car was on axle stands, it behaved like an open diff when I checked it?

As for the 'box - The ratios on the 6 speed are different, and I understand it has a 3.9 diff instead of a 4.1? (Which I guess the OBX diff is?)

You would swap your ring/pinion from your current setup, so the ratios would stay the same.

What makes you think it's a torsen then?

:bigtu:

My car's a '99 1800 RS - A JDM import, and they had them as standard from the factory. (That said, gawd knows what's been done to it over the past 12 years!!)

Believe it or not, this is my first RWD car with a (supposed) LSD - My Elise didn't have one (none do - It's an option for race cars), and neither did my Caterham. Most cars in the UK seem to be FWD...(!)

Hence the noobness - Back on topic! :)

what does the transmission have to do with the differential?

TorSen = Torque Sensing, with both wheels off the ground there's no torque therefore the diff acts as open.

Trust me your diff is fine, that LSD test is used in error a LOT on a TorSen.

As above, apparently the 6 speed box has a different ratio LSD to the 5 speed - In my ignorance, I didn't realise that it was the ring / pinion which determined this ratio and was interchangeable - It's the first car I've owned with an LSD fitted, so I've got a bit to learn it seems... ;)

I took that to mean, "it's been so long since I drove my torsen I have no idea how it drove, but I do like this new diff"

By old old I meant before the maruha which I had for one year. I do remember how it liked to track the car out on corner exit and this one let's me control where the car wants to go a lot easier.

To follow up: I finally installed it after avoiding it for months. I decided to just install it regardless of the ring gear flatness.

Backlash: I got it to .002" backlash at the high point, 0.006" backlash at the low point (spec is 0.0036 - 0.0043 i think.)

It drives fine, can't feel any ill effects of the goofy backlash. With the top up i can hear some quiet rear end hiss/whine that wasn't there before, but it hasn't gotten louder and isn't cyclical-sounding.

It does appear to lock really well. I haven't been able to drive too hard yet but I can tell it's working fine. Off the accelerator, it turns in like an open diff, under power it locks up the rear end as expected. Haven't gotten any 1-wheel-peel yet.

I'll keep you all updated if anything changes or explodes

I ordered one. I also ordered the washer/bolt kit and bought a 1.8 diff + shafts. I will install it this winter and might find some time to put the turbo on too.
Small question: I got the 1.8 diff from a NB with the shafts that slide into the diff. From what I understand these are 5mm wider. Do I need the uprights too?

https://www.miataturbo.net/attachmen...ine=1326072024

I'm considering buying one of these LSDs. For the OP and those who have also bought and installed one, how are they holding up? Thanks!

Still going strong after 6 months for me. Stock power though:giggle:

OP sold the car to me. The car has been off the road for a few months but all throughout the summer and for the couple times I autocrossed it, the LSD has been holding up awesomely. The car has been driven pretty hard with no signs of the LSD giving up - and thats on turbo power :)

Yeah it's a sweet deal and a great LSD. Just make sure the gears are installed the right way.

Who again was going to build me one?

Cheap ebay LSD and spring/bolt kit are winging their way (slowly) to me in Puerto Rico.

First of all, I apologize for the Necro Bump...

https://www.miataturbo.net/attachmen...ine=1407257729

..but I'm looking for any feedback from the last three years on people using these OBX LSDs. I'm trying to sort out what I want to do with my open diff, and dropping $500-$700 on a 150k (or unknown) mileage torsen doesn't seem smart if these OBX diffs are up to the task.

They can still be had all over the internets for about ~$360 shipped. Looks like the previously posted hard-ware upgrade is still available, or they can be had from this place: OBX Ltd. Slip Differential They also offer to inspect the diff and preform the upgrade for a $175 premium.

Thoughts? Torsens in decent shape seem to be getting harder and harder to find and a Giken totally blows away my budget.

Also interested as a maybe upgrade from a Torsen. (Or is it?)