NA6 VLSD Replacement Options

[MLambert19]

I apologize if this has been discussed at length previously, but I'm looking for information and input on possible replacements for the VLSD in my 1991.

I understand I can go full swap if I find a 99-2005 donor car with a 4.3 LSD Torsen unit, I'll need the driveshafts and all to make that work.

But what about other aftermarket options? Any feedback on the long-term effectiveness of clutch-type units?

Links to other sources, purchase options, etc. all appreciated.

Happy New Year everyone, -Matt

[Phatmiata]

How about this setup??

V8Roadsters Getrag Differential Conversion


This kit is for stock Miata transmission and PPF

http://www.v8roadsters.com/getrag-differential-conversion-1/


http://cdn6.bigcommerce.com/s-hbv2qirf/products/292/images/443/Installed__59730.1421954706.1280.1280.jpg




A complete rear upgrade with 400hp rated axles, upgraded drive shaft with serviceable universal joints.

The Getrag carrier is widely used in many GM vehicles with a broad range of power outputs and applications. Its light weight cast aluminum design utilizes a clutch style limited slip differential an assortment of ratios. The size of the carrier offers exhaust clearance for 3” and optimizes ground clearance. Our unique design utilizes the factory hangers to support the carrier and custom front mount to eliminate twist and flex without relying on the subframe brace mounting points. This design allows the use of the factory and after market braces and subframe connector.

Carrier and axle combinations for LSx and MX5 drive lines axle combinations are built from all new parts, no remanufactured or machined original parts are used. The components in each kit are designed to work together under their stated application. Offered with a choice of axle and driveshaft options. Your choice of hardness for polyurethane bushings and Grade 8 or better hardware.



Kit includes:

Drive shaft for Miata transmission to Getrag differential
Bolt in mounting system for Getrag differential to PPF
Upgraded PnP axles rated at 400WHP
Hardware for install
Template for PPF


We utilize the Getrag in our road course and street cars. When sourcing the Getrag look for the 2006-2008. The later models have casting and seal updates. G80 series limited slip GM part numbers: 3:23 - 25978162 3:42 - 25873500 3:73 - 25873497 3:90 - 25968531 . We offer new differentials for sale. Check our GM parts section.

[MLambert19]

With the closest ratio to stock being 3.90, I think I could buy a complete 3.90/4.1 Torsen swap for less money...

I'm just finding it difficult to track down a 4.3 Torsen swap setup nearby... wondering if something like this:http://www.tf-works.com/cusco-lsd-type-rs-1-5-way-rear-mazda-miata-1-6l/ Cusco plate-type unit would work well... weight savings by retaining 6" drive-train, etc.?

[Phatmiata]

the V8Roadsters one comes as a complete pumpkin with upgraded axles that can handle 400hp

While that cusco is nice you still need to have someone qualified to install it. That will probably cost $200 to install and you still have stock axles.

Not sure your goals but if you plan to go turbo later this seems like a great option. It's the one I'm considering.

[MLambert19]

With the 6-speed, or turbo power, or a built motor 3.9 gearing would be fine. I'm going to be running ITB's and 264 Cams on an otherwise largely-stock 1.6.

After doing more reading, it seems some people have ring & pinion failure with the 1.6 diff in relatively stock trim... so I guess I'll just keep hunting for a 1999-200? 4.3 LSD donor car...

[radmachine]

I made the switch from a 4.3 1.6 rear end to a 4.1 and hardly(if at all) notice a difference in the gearing. Most Na8 cars came torsen and will probably be easier to find. Or you could waste a bunch of time like I did and use a Ap1 s2000 diff with 1.8 gears and housing and mazdaspeed axles.

[90blue]

For cheap, try the gen II RX-7 clutch diff. You can pick it up at Pick-n-Pull for about $50. You may not need to rebuild it if you can find a low mileage model, just clean it. Get an open 4:10 Miata Diff with the aluminum carrier. Swap the ring gear to the RX-7 unit and set the clearances to 0.003" in the carrier. You need the 1.8 Drive shaft and axles as well.

[Rogue]

After destroying my second VLSD, I had to throw in a 4.1 Torsen and never looked back.
I was hung up wanting to keep my 4.3, but turned out it wasn't an issue.

[90blue]

Always liked your 93

[MLambert19]

Thanks for the options. I've been talking to the folks at Expoline Auto in NH and will likely source a 4.3 swap from them sometime.

I was just trying to complicate things to keep it simple... or something like that.

[Rogue]

Always liked your 93
Thank you, wait until you see this ex95M I'm building. ;)

[wannafbody]

VLSD's suck. Go Torsen for a quick hookup.