I just threw in a Cusco RS LSD last week (60% lock-up).

I've only had a couple of drives, but the rear is definitely more hooked and predictable over the OEM viscous.

The other positive is that so far there's ZERO noise.

 

Anyone running run in autox or on the track? Have you had to move roll stiffness forward? Any "going open" issues in low speed corners? Any curb hopping failures?

 

Bump for a good question.

The only input I've gotten is from an engineer friend. He said that a Quaife/Torsen can make a car tend to understeer on corner entry.

 

Yup, good question. After I got the Quaife, it does seem that my G understeers significantly more on sharp, tight, low speed turns. Like when making an immediate left at a 4 way stop sign.

 

The Quaife understeer issue is generally mild and only appears when moving from a non-LSD equipped car to one with an LSD. In comparison with clutch pack LSDs the Quaife reduces corner entry and power understeer. Having raced 240Zs and E36s with welded diffs, clutch pack LSDs, and Quaifes I can say that the Quaife pretty much elimiated corner entry understeer and made it much easier to put power down mid corner and at corner exit - as long as the suspension was tuned to take advantage of the power delivery characteristics of the Quaife.

Anyone tracking a 350Z with a Quaife?

 

I've tracked my 06 Z(base) with a Quaife. I did not get any one wheel spins on the particular track I went to (Thunderhill Raceway), but on the street with cold tires on a slow turn, it happens.

I love the Quaife!

 

As I am now in the market for a new LSD (my stock LSD is not holding up), I am debating between the Quaife and a clutch type. And money really isn't an issue - I am looking for performance on a road coarse from my Z!

I am leaning towards the Quaife as it will handle my hp (440rwhp) and will not have heat issues on track. Just would like more input to see what else I should be looking at. I don't drive my car on the street anymore and take it to road coarses about 1 to 2 times per month.

Input would be great!

 

Mooddude,
I've had the Quaife for a few months now and can give better info on it now. If you're going to do autocross on your car, it has to be well balanced. Since this is a torque sensing diff, it needs load on both wheels for it to work properly. For example, if you take a hard slow corner and you loose all traction on one of the rear wheels, the diff will not work and will act like an open diff. This is not the case with clutch type diffs.
This has not been an issue for me but i've heard of people having to setup there suspension to suit the Quaife.
I haven't done autocross events on my Z yet, but on the track(roadcourse) the Quaife works like a dream. I can only tell it's there when I floor it coming out of corner and the car just goes. Now with your 440whp, that'll be a bit different :-)
I really like this diff and I've called their tech support with questions and they've been very helpful. it doesn't hurt that it has a lifetime warranty as well, plus no parts that wear down. Basically you buy this thing and if it needs anything, it's covered.

 

I run the Quaife and have no complaints with its performance. 554whp, 690wtq.

 

I have the Quaife in both of my R-200 final drives for my 280 Vintage racer. If the rear has too large a bar, or the front too small the inside rear tire lift will be noticed right away as the Quaife has lost the torque input.

I just run the front bar and some stiffer springs on the front vs. rear. (East coast car) The next plan is to upgrade to a larger hollow bar and try to get a rear bar to work. If that works fine, if not it can't hurt to try.

So far jumping curbs has not broken anything. I try not to use the ones that make two wheels come off at once. Mainly just the ones that don't affect the drive forward.

Alan

 

In my experience the Quaife generated significantly more heat then the clutch pack LSD. The shearing forces placed on the fluid from the gears generates lots of heat.

 

Hmmm - I talked to Quaife and they said I would not have to provide cooling for the LSD.

So from your experience - if I got the Quaife would I have to add a pump and cooler? Since people who have clutch packs LSD and race a lot have to provide cooling.

 

I don't have any experience racing with the R200 (R230?) used on the 350Z. All my Nissan diff experience has been with the R180 in a 240Z. In either case (clutch pack LSD or Quaife) a diff cooler was needed when running 30 minute race sessions. Fluid temps exceeded 350 degrees and the housing itself was too hot to touch for about 20 minutes after a session (made diff swaps a *****). Before I installed the diff cooler I was running Swepco or Redline and changing it out after every weekend. After, I ran Swepco 201 and changed the fluild every couple months.

The R200/230 is physically larger so its a better heat sink. You can probably get away with no cooler if you're willing to change the fluid frequently and maybe a finned rear diff cover will help.

 

Thanks - and from your experience is the Quaife better than a clutch pack if you set the car up right?

 

I preferred it although your driving style has to change a little bit. You need to get used to putting a lot of power down earlier in a corner. After I installed the Quaife I could lift the inside front wheel off the ground in corners under power:

 

That is what I am looking for! I have already started to lift the front wheel on the Z, yet after about 2 laps - the stock VLSD can't handle it anymore and I just spin the inside tire.

 

After about 3 years of beating on my nismo LSD, I decided to take her apart and see what's inside. I've read too much conflicting information on what percentage lock it was set at from the factory, and I always felt that it was too strong for my road course use. I didn't care for the way it pushed/pulled on throttle and tugged at the steering wheel under acceleration, and it generated too much heat in my rear tires after a few hot laps. So,, here's my account of how to take out the diff and take it apart and re-arrange the clutch plates. I am by no means a talented mechanic and don't really know what I'm doing, so proceed at your own risk.
Big thanks to Z Car Garage for fielding my calls when I got stuck and helping me through the process.

 

step 1: Buy a lift. When you are done impressing your friends and neighbors by bringing the car up and down, up and down, proceed to get down to business.

 

The removal of the pumpkin is not too difficult. Just a few bolts here and there and it breaks free. Just be ready to catch a 90lb weight.

The removal of the lsd is not too hard with the use of a big hammer and pry bar. You can see from the third picture that the diff is set up as a 1.5 way.

The bolts that hold the ring gear on are loc-tited on and my cheap impact wrench would not get them off. Off to Z Car Garage for a little help.. I also used the excuse to stop at my friendly neighborhood sears an buy a new impact wrench with a bolt breaking 750lbs of torque for next time.

 

Now to crack open the case and see what configuration the plates are in. (yes I know that the nismo lsd is externally adjustable for break-away torque, but I don't feel that the adjustment was enough for me).

While things were apart, I did some research and found that a treatment was available to the plates that would not only strengthen the plates but would reduce the friction and decrease chatter. Check it out at http://www.wpctreatment.com/ and http://www.kaazonline.com/newproduct.html for more info.
For just over $100, I had my plates treated. Notice that the treated plates are a little lighter in color after the treatment.

The last picture shows that the 10 plates are originally configured for 100% lock, or ABABABABAB. I decided to re-arranged them and reduce the working surfaces from 9 to 7, or ABABBAABAB.

Put everthing back together in reverse order, and re-installed in the car.