Which is better for a street car with a possible autox future and why? The choice is between a Kaaz 1.5 way and an Apexi 2 way. What do you guys think?

 

I would suggest the 1.5 way.

The 1-way means that a differential would work only on acceleration. (Good for drag race applications)
The 2-way means that a differential would work on BOTH acceleration and deceleration.
The 1.5 way is a combination of the two, meaning the differential would work on acceleration and only partially on deceleration.

Just as a side note, you can also have the KAAZ diff adjusted (via internal discs) so that the "pick-up" can either engage sooner or later, depending on what you like.

For a normal street car w/ occassional autox,...the 1.5 would be fine. BTW, this is EXACTLY what the guys from KAAZ USA will tell you.

You just don't need 2 way diffs for street driving.

 

If you don't want to have to rebuild the diff occassionally, look into a Quaife gear diff. These are adjustable (much easier than the Kaaz, I might add), and you never have to open them to replenish fluids or friction disks. I think they also come with a lifetime warranty, if I remember correctly...

As far as quality goes, Quaife are at the very top of the ladder. You pay a bit more, but I believe it is worth the extra money to eliminate the wear issue.

 

How strong is tha KAAZ?? Wll it take 6000rpm launches
with ETstreets?

 

YES! I have never heard of anyone breaking a KAAZ.

 

your halfshafts may be a different story though.

 

I've heard of people breaking KAAZ LSD's.
I've never heard anyone breaking a Cusco LSD.

If you're talking FC or FD, try and get a Torsen (stock on FD). This has the most linear lock-up characteristics and almost zero maintenance. ALL clutch-type LSD's will require clutch plate replacement eventually.

If you're going aftermarket clutch-type, stick with 1.0 or 1.5 way for road racing. 2.0-ways are only for drifting.


-Ted

 

A friend of mine from Japan suggest me cusco 2 way for drag racing ? some one who use 2 way ?

 

i have nismo 2way in my s13. daily driven and no problems. i love this diff.

 

It doesn't make sense why you would want a 2 way diff for drag racing. For drag racing, you only need the differential to work when you are accelerating,...therefore you only need a 1 way diff.

 

So can i use the stock Torsen LSD for drag or not ? Why ( for example ) Ari use KAAZ 1.5 ?

 

Can you say "sponsorship"?


-Ted

 

As Ted said,...either:

1) Ari has a sponsorship.
2) Or the information that was provided (in a magazine or otherwise) was wrong. A lot of times, there are mistakes in magazines.
3) Ari uses the product because he wants to.

Ari doesn't need a 1.5 way diff. He doesn't need a 2 way diff. He "only" needs a 1 way diff. But that doesn't mean that he can't use any one of them.

 

I use KAAZ 1.5 way and it is the best diff ever

Can you guys show proof of a KAAZ diff ever breaking??
Ari has never broken his and he consistently runs 9's in the quarter mile with more than 600 RWHP.

93 FD

 

Several FD owners on the "big RX-7 mailing" list have grenaded theirs.
Sorry, I don't archive those messages.


-Ted

 

Anyone knows, how torsen works? One way, I guess... or not?

 

the stock torsen is not good for drag racing. It is a very weak differential and breaks on high rpm clutch drops with relitively low hp numbers. Not only that but people have tested before and after horsepower numbers with just changing the stock torsen out for the kaaz 1.5 lsd. One person made almost 30 more rwhp from changing over on a 400 rwhp car. That is pretty damn good.

 

Peter Farrell ran 9.9 in the 1/4 mile with a STOCK torsen LSD and it didn't break (with drag slicks). He also uses it on his IMSA race car also so it should hold up well if you have good drag slicks, but if you drag with street tires you will break the rear end.

 

Wouldnt slicks break the damn thing a lot quicker then street tires? Street tires mostly just spin.

 

Yeah, the IMSA car has a stock Torsen LSD.