LSD Info Needed
 

Im trying to put together my budget and build list. A LSD is a must for me. I'm current looking at the OS Giken differential. But I'm trying to recall from my 350 days what was also needed with a LSD on a base model Z? Just seems I somewhat have a vague memory of some additional parts from the dealer for base models. So I need your help here. Thanks.

automatic or manual? if manual then you will need some shims, with the clutch types you will also need fluid and the friction modifier for your diff.

Yea, it's going to be a manual. So shims then. Thank you.

Besides the optional shims (those are used for correcting the LSD alignment in the housing to prevent backlash) but the base model will need the longer stub shafts unless you buy an LSD that is designed for the base model.

Now that you say that, it seems I somewhat recall this now.

most of the lsd's are designed for the base, but yeah if you buy a sport model one you need a stub for a sport, if you buy a base model one you don't need anything. I bought a quaife and they pretty much only make the base model one, so i had to wait 3 months for nissan to send me a base axel stub.

The os giken falls into that category if you have a base your golden if your sport your screwed.

I think Quaife has 2 models available now, one as an open diff replacement and one as a viscous unit replacement. As you said OS Giken is designed to replace the open diff so you need the base stub shaft for that one. The Carbonetics (clutch type) is designed to replace the viscous unit.

This is really good to know, I planned on getting a base with this in mind so I am happy I do not need anything to fit the Quaife into the base differential.

yeah it's hard to find the quaife sport one, they have both been out since 2003 as they are the exact ones used on the 350, also the quaife sport model diff requires you to not only have the longer viscous stub shaft but you also have to cut the end off it and grind on a camfer. The damn thing comes with a print showing you how to modify the stub. but if you get the base one you can't just cut the end off the sport shaft you have to get the base stub. they make one for the automatic case and gear too, tho i'm not 100% on if that one will fit the 370. i think it is something like the QD12f(manual requires base stubs) QD13f(manual requires modified sport stubs) QD11F(automatic base stubs)

At one point last year i was told there haven't been any sport ones imported in a while

The quaife differntials are similar to (or the same as?) the torsen units are right? Does torsen make one that we can use? Seems to me that a torque sensing type would be the best choice right?

i just answered this in another thread yeah the quaife is a helical type. they don't lock as hard as a clutch type but in my opinion they feel better and are a better street/track differential.

Don't consider the clutch type locking action to be absolute, the amount of lock can be adjusted by varying the amount of slip additive. The hardcore folk actually rebuild the differentials with extra clutches for a stronger locking action, not necessary for us mere mortals. The clutch type differentials are better suited for track use, they don't generate as much heat as a torsen style differential, they last longer, are more predictable (if you lift a wheel or spin both wheels) and can be more easily rebuilt. The downside is that you have to do diff oil changes frequently.

The torsen style are very smooth for the street, and gives much more torque transfer than a viscous unit.

don't forget the quaife lifetime warranty, so long as you keep fluid in it your good.

Lifetime. That's pretty awesome. Can't really believe these LSD last so long without being rebuilt within some years.

HOW ABOUT FOR ThE GUYS WITH AN AUTO!?!?! lol

Torsen (the brand) has a lifetime warranty but if you try to exercise it more than once they start getting pretty rude. They were a very popular add on for the Mustang but folk that tracked their cars used to tear them up in pretty short order.

Quaife uses the Torsen basic design but has taken it to the next level, I haven't heard any reported failures from them yet.

How difficult is it to install an LSD (I searched and couldn't find anything)? Something I could attempt myself with average mechanical skill, or better to be left to a professional? I too am interested in an aftermarket LSD for my non-sport Z at some point down the road.

The actual installation procedure isn't that difficult but requires a few specialized tools. Adjusting of the backlash and checking the axle shaft's for run out is why you want a professional to do it. My race shop mechanic wouldn't even touch it, he referred me to a machine shop.

Could you elaborate on that?

Also I'm surprised to hear a clutch style differential would have less slippage, I thought that was the exact opposite. I'm not even sure how an LSD with gears could slip, I know they do though, I've seen it :facepalm:

I'm not very far away from you, if you take the plunge I would be very interested to hear where you went and your thoughts of the entire ordeal :D

Or maybe we can get a discount it we have two installed :tup:

It's not slip per-se, but a built in torque bias ratio.
Here is a white paper on how the torsen works.
The development of a differential for the improvement of traction control

Yeah being a machinist helps to put one in, i had to bust out the 2" indicator, the torque-angle gauge, and the last word, as well as some bluing to check mesh. At least you don't need a case spreader like certain domestic cars rear ends. definitly a precision job though and hope to hell your pinion height doesn't change or you're in for some more cash for bearings and a crush sleeve and more shims.

OK, now I get the Tobyharlem location!:roflpuke2: This probably won't happen for awhile (if at all) but I'll keep you posted. :tup:

You might as well have said I'd need a flux capacitor! I'm convinced...it will be a qualified shop that does the install if I take the leap :icon17:

I hear you, right now I'm just looking because I know I will want one. So we'll see how long the ol will power can hold out :rofl2:

I finally got to read this, good stuff :tup: