Quaife ATB Differential for 350Z
 

There have been other threads about the benefits of this type of differential, as well as the shortcomings of the viscous unit as delivered in our cars.

I spoke with a representative at Quaife USA today, and they don't have our application in process at this time. He recommended that I check back in the Spring to see if anything has been begun. He also said, however, that if I could drum up enough interest, it would speed up the process substantially. From what I've been told, they would produce these in lots of 25 units, so if we could confim at least a portion of these for immediate sales, this could happen very quickly.

Is anyone seriously interested in this?

Mark

I've tried Quaifes and I was not that impressed. They only transfer torque so no good for drag racing and only so so for road racing. Give me a clutch type anyday. Clutch type is both stronger and also much better for drag racing and serious road racing. It's also tunable for your needs unlike the Qauife. Lastly, it's a LOT cheaper.

I don't think you really understand how these differentials work.

When you say they "only transfer torque so no good for drag racing and only so so for road racing", that doesn't make sense.

A clutch-type limited slip operates by locking the wheels together with a certain amount of preload on the friction plates in the diff. In order to be able to go around corners without dragging wheels, there are ramps which then help to overcome this preload and allow the wheels to move independently of one another. With this arrangement, while the wheels are locked, each wheel receives an equal amount of torque, regardless of the relative traction of each wheel. While this is fine for drag racing when it's just in a straight line, it is less-than-optimal for handling.

On a torque-biasing diff such as the Quaife, it drives both wheels, but actually distributes a greater amount of torque to the wheel that has more traction (up to 4 times as much as the other wheel). This is especially useful in a vehicle used for going around corners, as weight transfer and other factors affect how much relative traction each wheel has. This type of differential is VASTLY superior for road racing purposes.

Also your statement that a clutch type is stronger is not necessarily true either, and it's really not much cheaper. Look at the prices of KAAZ units compared to those offered by Quaife.

What kind of price tag are we looking at for the Quaife? You dont have to be too specific, just a range.

Thanks

Another disadvantage of the clutch types is that you have to replace the clutches while the Quaife is virtually maintance free. However, it is true that clutch types do have no torque transfering abilities. For a street car, however, I dont think it's worth the hastle of having to take your LSD and replace clutches every 10000-15000 miles.

Here try this. http://www.howstuffworks.com/differential.htm
The Quaife is like a Torsen. The plates on a clutch type do need replacing eventually but I've ever seen one need them yet after years of trouble free use. Another nice thing is that if they do fail, it simply stops working. The Quaife and other gear type difs often destroy many other parts when they let go. Not good. For drag no contest, a locked differential like a clutch type is much better along with the added strength. This is also the case with snow or mud (im real word situations). The Quaife can only transfer torque. It does not work properly if even one tire loses traction (like snow, mud or spinning tires etc. . . ) whereas the clutch type will lock the two sides together improving grip. For road racing, the choice is simple. The Quaife is only 1 way dif. The clutch type can be configured for 1, 1.5 or 2 way operation and on top of that most allow you to dial in how much lock you want from 30-100% making it a much more tunable dif for the real hardcore road racer. It's more aggressive under most settings than the Quaife and the 2 way operation helps braking whereas the Quaife does nothing. As for pricing, the Quaife retail is pretty much what you're going to pay. The clutch type units are cheaper for the most part street price.

CUSCO has type types out also. Both 1 + 2 way. They run around $900.