smg944

iTrader: (34)

my s4 t2 diff is slipping when i do a burn out in the water box. so i cant get my slicks heated. is it better to rebuild my diff or get a kaaz? also what parts other then the clutch packs should i change if i decide to rebuild. i should be just under 500whp on race fuel for this upcoming season.

IRPerformance

iTrader: (41)

A Kaaz will be stronger but noisy. I personally can't stand the clunking and noise. I'm sure you can't even tell the difference between the stock torsen and turbo 2 diff. If you drive the car on the street I would recommend staying with the t 2 diff and rebuilding it.

pistones

iTrader: (5)

i agree, i drove an s14 with a kaaz and it popped and clunked so bad it felt like the diff was blown. not recommended for street, it will drive you nuts. mazdatrix does sell a thicker clutch pack kit for S4 diffs. i would recommend rebuilding it with some thicker plates if you want something more aggressive.

arghx

iTrader: (3)

I've been in an FD with a Kaaz. It is indeed annoying. Imagine explaining that to every passenger you have.

smg944

iTrader: (34)

thanks for the imput guys. yea my car is mostly street anyway. ill check out mazdatrix for the clutch packs. is there a guide on what parts are needed to rebuild it?

beefhole

iTrader: (29)

^I'm in the same boat as you. While my car is down, I'm thinking of turning my TII diff back into a real LSD and not a 1 tire fryer. I looked on mazdatrix. The Kaaz is around $950 if I recall, and the mazda unit is near $1100!

They say you can get some coating on the Kaaz parts and it's quiet? Can anyone confirm? Either way I am not spending that kind of money on a diff...

So I started looking at parts cost for the TII diff. You need "6 of these, 4 of those yada yada" . OK I need 6 of... $39?! And 4 of $WTF!?

How much does a rebuild cost if you go to a shop? The prices are absurd!

smg944

iTrader: (34)

looks like $640 for the parts only from mazdatrix.

Busted7

Are you guys useing the posi additive to keep them from slipping?

smg944

iTrader: (34)

^ i believe i put that in. it came in a small bottle.

proz07

iTrader: (6)

i dont have a sugestion but i do have kaaz sitting around but i do hear alot about how loud it is. So how loud is it really? Im dynamatting the whole car so....
z

beefhole

iTrader: (29)

Yeah... that turns me off of getting it rebuilt.

Busted7

So far i dont have problems but i have two diffs one with 410 and the other with 430. I also use the royal purple with the additive already in it.

You might just try ti buy a diffrent diff its cheaper!
I got 1 from japan2la its low milage.

smg944

iTrader: (34)

correction... all parts from malloy mazda would be $480. these include the thicker washers and disks for stronger clamping. i am going to go ahead and rebuild it. what about axles? time for some 300m chromoly's or are the stocks still ok. i am shooting for 500whp soon.

GoodfellaFD3S

iTrader: (213)

I lucked out and found a brand new s4 TII diff back in 2002 and had the entire thing cryo-treated. I barely drag race, but nothing like over-building your car just in case

Btw, I've never really noticed a difference on the street vs my old Torsen diff.

AnthonyNYC

iTrader: (3)

Kaaz has clutch packs that now make very little noise. They are treated and are more expensive. I bought them about 2 years and swapped out the old ones.

Anthony

pistones

iTrader: (5)

what kind of mileage do the Kaaz's last to? if it is near 50k then it should be about the same mileage as a TII. From what i hear, the Kaaz LSD is tuneable. which means you can take out some of the discs to make it lock up less for less noise, but it won't be as aggressive in engagement. i will probably rebuild mine, since i have two spares while the torsen is in use.
So how much is the new Kaaz with the quiet clutches? i still think rebuilding the stocker will be more economical.

silverfdturbo6port

iTrader: (26)

kaaz is like ahving a lincoln locker lol but a kaaz is bad *** if your into racing or drifting not very probable for the street. you will be wearing your tires out and putting some stress on bearings by driving around town with tight turns

hsitko

iTrader: (1)

Kaaz now has a qt model diff that has different clutches. The advantages are less noise, lower heat produced, and no break in period. I have one on my car and it really doesnt make much noise at all. I like it a lot. It isnt that much more expensive than the normal one.

Dudemaaanownsanrx7

iTrader: (23)

Just saw this thread. I did a s4 TII swap into my FD last week. I did tons and tons of research before doing the swap and have a good understanding of the options available

My advice is to pull the differential out, take it apart, and measure the friction disks and thrust washers. There are 6 disks and 2 washers, the FSM says the disks should measure out between 1.9 - 2 mm but this is wrong (those measurements are for the non turbo model LSD), according to the mazda motorsports website the new disks are 1.75mm and the oversized disks are 1.85.

At first I thought I would need all new disks until I found the discrepancy between MMS and the FSM. So in spec would be between 1.65-1.75mm for stock disks. Measure all the disks individually, as well as stacked (read the fsm on how to get the stacked measurements) and see where they stand, if they're in spec then you can add shims out of aluminum cans, or alum sheet... beer, soda, and brake cleaner cans work well according to the auto-x guys on the MX5 forum. The extra shims increase the lockup pressure of the differential to either freshin it up to stock or even provide more lockup then stock if desired.

If the disks and/or thrust washers are out of spec then the 6 disks and 2 washers should be under $250, and even cheaper if you have a mazda motorsports account.

I use royal purple in my differential with the additive already in it as well. If you're fluid is old getting fresh fluid can make a difference. The clutch type differentials should be changed more frequently especially with lots of racing.

You will also want to check your backlash when you take it all apart, and mark all the bearing caps, shims, bearing races ect exactly as they came out. When I did my swap I checked the stock differential's backlash and it had way more backlash then what the FSM suggests (most likely from wear), this created slop in the drivetrain and made it clunky between shifts and throttle input changes. Amazingly the TII LSD was ever so slightly wider then the torsion and I was able to use the same shims as before to set the backlash just a tad tighter then FSM spec, which works out perfectly cause as everything seats and wears in the backlash will be right where it needs to be. My drivetrain is now nice and tight with no clunks taking of from a stop or shifting gears.

Replace the axels when they break, they aren't that hard to get out and you may not have any trouble for awhile or maybe ever. If it aint broke don't fix it. Then you can keep an eye out for good deals as they come along. If money isn't an issue then buying the best all at once isnt an issue. I'm very frugal with my money and still end up spending large amounts of money on the car.

Dudemaaanownsanrx7

iTrader: (23)

Actually the additive is to allow them to slip not keep them from slipping. Otherwise the clutches can become grabby, make noises or cause bucking especially when turning. Adding more friction modifier or having an oil that has a lot of friction modifier will make the clutches slip even more, providing LESS lockup. The key is to balance maximum friction and lock up without making them grabby on turns. Something you will know by the noises it makes.

So for anyone having lockup problems, you can try replacing the fluid with new fluid that either contains no friction modifiers in it, then if you have issues with the clutches grabbing add the GM friction modifer in a little at a time. Or you could try to find out what brands have lower amounts of friction modifier and try them. Redline suggests replacing some of their oil with non LSD oil if you need more lockup. I'm sure this would work with other oils as well.

Busted7

^^^^