For the roadracers out there...anyone using the KAAZ? Talking to the folks at Rotary Performance, they said one of their customers uses the KAAZ but loosened it up a bit. Other than the KAAZ, there doesn't seem to be much available except for the RE rear diff but I have no info on that concerning any increase in strength. I'm really interested in running something stronger for the drag strip yet something that's not going to induce handling issues on a road course. Any thoughts?
Michel
95RX7

 

I don't know anything about their applicability for road racing, but Mazdaspeed offers some additional options. I attached a scan of page 156 from the 99 catalog:

 

I've heard Cusco units are superior over the KAAZ units.&nbsp Cusco LSD's can be bought from any GReddy dealer...


-Ted

 

Are either the Mazdaspeed or the Cusco stronger than the stock unit? Are they going to hold up under 5000 rpm launches?
Michel

 

Rotary Performance hasnt been able to break their Kaaz Unit running 9-10 second passes in their FD. I cant speak for the other 2 units but someone mentioned its stronger than the Kaaz so I would think its pretty tough. The stock diff is a joke and will crap out on you with some nice wheel hop.

 

It depends, what type of LSD are you gonna get? Is it going to be 1 way, 1.5 way or 2 way? It also depends on your driving style s well. The stock LSD is a torsen unit-very good and high quality for road race. Switching to a mechanical one is very good as well a a lot of japanese tuners choose this route. A 1 way LSD works when you have your foot on the throttle, a 1.5 way LSD work sometimes when your foot ison the throttle and sometimes when it's not, a 2 way LSD works all the time regardless of whether or not you are on the accelerator. I road race my car and I plan on getting a Mazdaspeed 2 way LSD from corksport. I never drag race my car so I couldn't tell you which would be best, but my friend has the KAAZ (he drags a civic that runs 11's) and he broke it. I hear the cusco one is very good and so is the Mazdaspeed one for road racing.

 

That was a little vague on what exactly the difference between a 1-, 1.5, 2-way LSD works...

1-way - locks up only on acceleration
2-way - locks up on acceleration and decceleration (i.e. full-time)
1.5-way - locks up on acceleration but partially locks up deceleration



-Ted

 

I use CUSCO.
It has better quality.
RE AMEMIYA's diff is good, but it's chattering noise is big.
If you want to get Cusco, KAAZ or RE AMEMIYA,
I will be able to offer you at a good price.
Because they are our race partner.

 

thanks for clearing it up, I knew it went something like that..

 

you might want to take a look at this link as well.

http://www.gurumotorsports.com

a friend of my recently bought one of there torsen diffs.

the things is almost to pretty to put in a car. so fare he is very happy with it and its been a big improvement over the factory unit. but this is comparing a stock modified lsd unit from a 1st gen car. they make them for all year rx-7s including the 3rd gen.

there diff is suppose to handel high horsepower. and these guys do a lot of roadracing so you might want to look into it. for the price its around the same as the kazz. from what i have seen they do high quality work.

James
93 mbm

 

Ok so let's revisit to see if I'm understanding this correctly...

Our stock torsen is a non-mechanical, meaning it relies on fluid for lockup? Or is it in the gears themselves? The others, KAAZ, Cusco, MS, RE, are all plate-types, hence the noise going around corners

The stock Torsen is what, at 1.5way? I noticed when I had the car corner balanced that turning one wheel does not cause the other to turn in the opposite direction. The shop doing the work was a bit surprised by this fact and it wasnt' until the drive shaft was turned that the above happened, both wheels turning, one in the opposite direction.

Anyway...in everyone's opinion, what's going to be the best compromise between roadracing ability and drag ability? It sounds as if the 2 way would be the best with, if I'm reading this correctly, the best amount of traction under acceleration and braking. How does a two way affect cornering?

So the Cusco seems to be of higher quality. What sort of price and I looking at and will it work with RP's upgraded chromoly axles? I'll check out the Guru stuff as well.
Thanks!
Michel

 

Stock FD uses a Torsen.&nbsp The Torsen is also known as a "helical" LSD - it uses a set of planetary(?) worm gears to engage and disengage itself.&nbsp It does not rely on fluid - at least unlike a viscous LSD.


That is correct - they are "clutch-type" LSD's.


I believe most Torsens are 1-way only.


It really depends on your driving style...I'd recommend going with the 1.5-way or 1-way first.&nbsp The 2-way is really for drifting, cause any sudden release of the gas pedal will cause the rear tires to lock up suddenly/slightly - good for swinging the tail out!&nbsp Try to get in touch with Steve Kan - he used to run a 2-way and hated it (initially).


It's a stock replacement, so if you're running a stock diff or any stock replacement diff, it'll work.&nbsp The diff, typically, has nothing to do with the half shafts, unless you changed the stub axles out the of the diff?&nbsp The Cusco LSD full retails for over $1,000, but street prices are in the $9xx...



-Ted

 

Ok, so a 1 or a 1.5 way will make the car a little more stable for me on a road course assuming I'm not into getting into the turn sideways first :-)

What are the main handling disadvantages to the plate system versus the torsen type? I believe the new M3 uses a variation on the Torsen as well, no?

 

When I have LSD questions, I go to http://www.club4ag.com/faq%20and%20t...ential_101.htm for answers.
club4ag.com : a damn good site.

jerk_racer@hotmail.com

 

Excellent! Thanks for the link.
Michel

 

I have the RE Amemiya Diff for a while it's good and I have noticed better hooking on the line and better tracking while running down the 1/4. Yeah it makes a chatter while turning tight, easy way around this is to just get off the gas while busting U-turns, lol.

 

Lock-up ramp - the Torsen has the most linear lock-up ramp.&nbsp I don't have pics or a site that has these depicted graphically, so I'll try my best to describe them.

The Torsen locks up linearly - the ramp is basically a diagonal line.&nbsp The clutch-type is two intersecting diagonal lines with differing slopes.&nbsp It's relatively shallow before the full lock-up point.&nbsp After the lock-up point, the line climbs faster with a steeper slope.&nbsp What it comes down to is that the Torsen is a much more predictable LSD back there.


-Ted

 

This should make a lot more sense...





-Ted

 

And no one makes an upgraded Torsen for our cars that would meet my criteria for strength and handling? Is it simply difficult and/or very expensive to make such a unit or is it simply impossible?
Michel

 

Ignore that last post...I just looked at the Guru diff which is $795USD, basically a stronger Torsen diff for the third gen that uses all new components, not just a strengthened stock unit like the Mazdaspeed. The Cuscos seem to be running around $1100USD and change. I may give the Guru a try.
Michel

 

I've read over the page a bit more thoroughly and even Guru is planning an upgraded plate-style for the third gen. Hrm...Me thinks it's time to send them an email.
Michel

 

Cusco is around US$1100 in USA ????
I can offer you at US$800 including tax and shipping(from SFO,CA)

 

inukai,
Thanks! I'll contact you if I decide to go with the Cusco. I'm going to give Guru a shout to see what they have to say about the upgraded torsen.
Michel

 

Ted, your picture isn't working.
And are all torsens one way or just most (stock)
Wheres twister when you need him

 

Damnit, I thought this thread was buried - I pulled the pic off the website already.&nbsp Too bad!



-Ted