how much hp must you be pushing in order to need a KAAZ diff? if you never use slicks/drag radials at the track, will you need the KAAZ differential??

 

Joe,
The hp doesn't matter. Gordon Monson pushes over 425rwhp and still uses the stock diff.
BUT if you drag race at all, its a must as the stock diff sucks *** for drag racing. If you get wheel hop more than a few times, kiss you diff goodbye.
If you do not drag race, then its not of concern for you.
Ernie

 

Very true... you don't really need a KAAZ differential unless you're drag racing. That's how i blew my stock differential. Stripped the final drive gears too. Now i have a kaaz.

 

What exactly destroys the stock rear diff.? If it is wheel hop will using slicks help preserve the diff.? I will be drag racing my car at least 15 times next summer so obviously I'm concerned. How much does a Kaaz diff. run, and does anyone have a link??
Thanks

 

Here's their website http://www.kaazusa.com/ . Jason sells them at the RX-7 Store for about $800, which is a pretty good price. The big advantage to the Kaaz is obviously it's strength, but also if you break an axle (which you will...) you can still drive the car. With the stock LSD once you snap an axle, your not going anywhere. The only drawbacks that I can see are that it is slightly more noisy than the stock diff, and requires frequent fluid changes.

 

Ok, I've made around 50 passes on the stock diff pushing around 300 hp at the motor on street tires. I'm now making almost 400 at the motor and am going to the strip on Friday to make some runs (also on street tires).

I don't want to break my diff b/c there is *no way* I can afford to replace it at this point. I'd be riding a bicycle .

I guess I'll go to the strip and not launch. I'll still beat all the slow as hell V8's

 

With street tires you should be ok, because they'll slip (note the word "should"...). If you had drag radials or something, I'd be more concerned.

While the diff itself is only $800, you need to take into account the labor. I had the diff done along with 4.33's at the same time (may as well get any gearing done at the same time, save what you can... and I had 3.90's still in there from when I was an automatic...), and the whole package cost and arm and a ******* leg.

 

so do you guys think the KAAZ rear end would be necessary in a 400 RWHP FD, with the occasional burnouts/donuts for show and hard launches on the street burning C5's and Supras???

 

I'm just getting my Kazz installed now... The Dealership is still
looking for shims that hold the Kazz in the new Housing I bought.

The old one cracked right down the middle when the diff. blew up. I was launching at about 6500 rpm w/ drag radials. However I must have gotten over 120 launches on the factory diff. Some with Drag radials and some with street tire.

If you're serious about Drag racing. Get this diff. installed before you blow up something. I had to buy a new Housing/ring and pinion/ and also the Kazz. This is more than a engine rebuild.
Including the labour. About 8-10 hrs.

Buy the way... Does anyone know where to get these shims?
And will the Pinion gear need one as well? thanks jc.