Is there such a thing? What is the 85 LSD? Locking or non locking? TIA

 

Limited Slip by definition is a locking diff. The 'limited' refers to how much slip the clutches will allow before the differential locks to transmit power to both wheels instead of to the one with the least traction as in a conventional 'open' diff.

A Gleason TorSen differential, in contrast, mechanically transfers power to the wheel with the MOST traction.

 

85rx7gs: are you talking about a fully locked diff like you can find on some large farm tractors and other off road vehicles? I think some SUV's have fully locking diffs that are activated by a switch. Our cars along with most other LSD equipped street cars is just that, limited slip, if you try hard enough you can still break just one wheel loose, especially if the rear is old and worn.

 

I was reading someplace about the LSD in the Rx-7 as being non-locking, from one source, and locking from another source. That's what got me confused, I think

 

gurumotorsports.com have a tech article about the torsen style diff and how they work.

ive got one on my car and they are some much more "drivable" in all conditions compared to a typical LSD. theres no suprises in the wet going around roundabouts as example.

 

TorSens are by far superior to viscous coupling LSDs.

 

Oh great...I really don't need any suprises. It must be a pain in the snow and rain. How much did you pay for the torsen style?

 

mine was $1500 aussie dollars, they list them for $US795 on their website.

Here in Australia a 2nd hand mazda LSD sell for upto $900! and they are rare as.. thats for a 17y.o+ diff which makes the Guru diff seam much better value when you consider its all new and made from billet steel.
I didnt want to put into my car it looked so good!
still not chaep but you get what you pay for

 

A search should yeild other diff options from other makes. I'm certain that some of the posts will tell which Miata diffs to go after in the local yard.
But do the research before diving into differential surgery. It's tricky business, they all say.

Manntis, twice you refered to it as "TorSen. Was that a type error, or is there really a capital 'S' in the name?

 

Torsen or TorSen is an abbreviation for Torque sensitive

 

They're the same thing, as Adsys01 noted above

 

Wow ... and all this time I just assumed it referred to a person. Because until recent years, I only saw TorSen's mentioned as "Gleason-Torsen" ... so I figured it was pair of people

Ya' live, and learn, eh ...

 

I believe Gleason was the TorSen inventor, as MacPherson invented the front shock strut with integrated steering, Watts invented a live axle linkage, etc.

 

Ohhhhh, I see!

Hey, I was wondering...I just put those ridiculous 265s on my rear end. (Just for fun.) I was wondering what really wide tires do to the LSD. Does it act differently? Wear faster? Work better?

I'm trying to figure out why my car seems sluggish...The tires are the same diameter as the others I replaced them with. Maybe I'm just not spinning as much now?
(stock 12A w/Yaw and header, aluminum flywheel- maybe 150 or so HP)

 

Did you change the offset, or just let all the extra width go to the outside? If the latter your suspension geometry will be a bit screwy.

 

That really was'nt the question. It is all on the outside (not a helluva lot I could do 'bout it); and I already know the geometry is fucked up.

...Shall I resubmitt?

 

the wider tires also increase unsprung mass, making the axle work harder just to spin the wheels up to speed on acceleration. I'm not sure if it's enough of a difference to create the 'sluggish' feeling you're encountering...

 

The 94+ Miata pumpkin supposedly bolts right up, but you've gotta saw off some kinda small bracket thats on it. It also supposedly has the same driveshaft yoke and axle splines. Only the Touring or "R" package Miatas have the TorSen diff, but you also get 4.30 ring and pinion gears to boot.