In all honesty, I've not done any test work on a Quaife unit myself. But I'd agree that you'd probably be satisfied with either in a street car. In normal driving, its true that you probably feel a difference in the bias level either. But that's not to say you'd never see/feel it.
The reason that this unit was designed in the first place is that FRPP was building the FR200 cars, and on their test mules, the Quaife they were using didn't provide enough tractive effort. When launching the car on the drag strip, the high torque level they were generating would overwhelm the bias level of the diff, and one wheel would spin. The diff would then transfer torque to the other side, and that one would spin instead. Back and forth. The whole time the car was trying to twitch back and forth, left to right. Keep in mind that this was in a Focus, turboed at 18 psi making 285 lb-ft, and using an SLA front suspension conversion, so how you apply that is up to you.
With the Torsen in place, the car launch straight without one-wheel spin. It just went down the track. That's part of what the difference is. Also, in tight corners, you'd pick up the difference in bias level once you've started approaching traction limits. I'd guess that you could transfer 10-15% more weight off of the inside tyre before the diff would allow spin to occur. So it is advantageous in an autoX.
Regarding strength, I don't know. To be honest, the Quaife is likely to be somewhat stronger, as I suspect it has more planet gear sets to distribute the load over. That said, I was unable to varify the ultimate strength of our unit because I broke axle shafts on our test machine before damaging the diff. The axle shaft broke at about 16% more torque then the open diff broke at. So either unit is strong enough to shift the weak link elsewhere.
Did I miss anything?
Last edited by TorsenRick; 04/28/03 05:41 PM.
