Life Span of KAAZ clutch plates

[Sandro]

I have a KAAZ in my Rabbit.

I broke an axle and after it broke the car was not able to limp under its own power. With a KAAZ it should correct? thats the whole point of the diff, transfer the power to the wheel with grip correct?

I am assuming the clutch plates must be worn. The diff has 6 weekends on it, would that be time for new clutch plates already or does that seem a little soon?

How long are your clutch plates lasting?

[Greg Amy]

It also has a lot to do with the breakaway torque, Sandro. Depending on how your diff is set up, there may not be THAT much torque bias in the spring plates. In fact, most retail-available LSDs are intentionally setup with minimal spring pressure so that they're streetable (think the logical extreme: the welded diff). My NX's clutch-type LSD would always spin free when I hopped curbs; your recent experience simply affirms that limitation to be expected from street LSDs.

For racing applications, it's very important to consider re-springing your clutch packs to better suit the racing environment, assuming you have the knowledge/experience base.

[Sandro]

Greg its starting to make sense.

I was looking at some data from when the diff was 3 weekends old(first time with data logger) and noticed going through a chicane hopping curbs the data was showing a small jump in RPM.

Plus the weekend when the axle broke, I actually set my fastest lap time at the track so it would seem a little odd if my fastest lap time was with an almost open diff.

I guess I was just assuming it would provide enough bias to drive. :018:

by re-springing the clutch packs do you mean installing clutch packs that are thicker?

[Greg Amy]

by re-springing the clutch packs do you mean installing clutch packs that are thicker?
I don't know the Kaaz design specifically, so I suggest you contact them. The NisMo LSD i was running I *think* is a comparable design, and it relies in differing springs/spring rates...

[bonespec]

No springs in a Kaaz LSD, just ramps.

Without torque on the other axle it won't lock up, sorta like a Quaife.

My Kaaz lasted 50k miles on the street, autox, and drag racing when I finally broke both drive plates on one side.

http://i107.photobucket.com/albums/m307/bonespec/Transmission/D%20Series/My%20Kaaz%2050k%20miles/P7020014.jpg

I don't have any pics of when I tore it apart, but might be rebuilding it over the winter to sell to a ITB/ITC Honda Racer.

From KaazUSA website

http://www.kaazusa.com/lsdcomponentsimage.gif

[Greg Amy]

Ah, then that makes perfect sense. Yup, without springs there's no way that a LSD will "LS" without some sort of torque bias. Which is *exactly* why I believe the Quaife - and now, the Kaaz - is the wrong design for racing.

I'm a "sprung-clutch LSD" man - or spooler - for auto racing, all the way...

[seckerich]

The last part on the outside of that diagram is a bellville washer (spring) and puts a small preload on the spring pack. To see what it has you need to measure the stack height (need micrometer, depth mic, etc) and see how much that spring is collapsed. As the packs wear you loose preload quick because of the short travel length and it needs to be reset. The ramps only work when both wheels are touching pavement so you now have wheel spin over the bumps.

[karter74]

Edit- I was reminded that because it is cam type load it may free spin under light load. Limping back in may not give it enough load to lock the clutches.

I will say I did some curb hopping with mine and no wheel spin at all.

[Sandro]

I emailed Bill, at Bildon and he brought up a valid point that

"If you apply torque to the diff (accelerate) then the pins will ride up the
ramps and lock the diff plates. The more you apply the throttle the more it
will lock. Only if you lift off will the clutches release and allow the
axles to rotate independently."

so basically with the broken axle I couldn't get the plates to lock. Which makes sense.

[bonespec]

<<< Got towed a mile back to the shop with a bad axle in my Kaaz tranny.


I guess I was having too much fun in the snow that night :)

[chewy8000]

Sandro,

I ran mine all season with no issues in the MKIII golf. I will most likely rebuild it over the winter though. One issue I did notice and you will as well with that trans is the output shafts have a ton of play in them. I contacted KAAZ several times and they said it's normal? I don't think it's normal that it eats output shaft seals and my trans leaks constantly... :blink:

[Sandro]

Are you referring to when you press the output shafts onto the spider gears you end up with play?

I remember having that problem, and asked KAAZ and Bill, and neither could help. I ended up doing something to fix it but for the life of me can't remember. (I think I might have used a different cir clip) I don't have endplay and it doesn't leak.

But your using an 02A right? so maybe something is different in relation to output shafts on 020.

Going to test breakaway torque this weekend and will post my findings.

[Flyinglizard]

Try fitting the diff with two case gaskets. The bearing stack height increases that way and can take out some output shaft slop. Or, work the side bearings until the clearance is reduced. Of course, use the late drive flanges that are "press on" They leak less. We always test fit the diff stuff to elimnate this slop. Of course, I always race with a welded diff also, (so I dont know shit.) MM

[Mike Mackaman]

On the Nismo and Power Brute clutch type limited slips, the bellville washer like Steve mentioned puts the pressure on. The standard breakaway is not enough for racing. The standard deal is to put a shim between the case halves and the bellville washers. I have driven a couple laps at Road Atlanta with a early stub axle and a late companion flange, which means zero drive. The only time it slipped was over the rumble strips on the exit of 5. If the clutch plates have the teeth broken off like this, that is your problem, you have like 20% less clamping force with each plate that is damaged. I recently remaired one for a customer that had almost no breakaway torque. Found two shattered clutch discs on one side. Replaced the two discs with some from another spare and it is back to where it should be. Has your car been involved in an accident or an off course excursion prior to the loss of drive? The one I redid was due to an accident.

Mike

[rx7chris]

Anybody ever try a wave trac or peloquin? Do they do the same thing?