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*To*: quattro@coimbra.ans.net*Subject*: cf*From*: QSHIPQ <QSHIPQ@aol.com>*Date*: Wed, 4 Mar 1998 11:20:16 EST*Sender*: owner-quattro@coimbra.ans.net

Dave E.: Locked center, Trg = 300, BR 50/50 split = 1:1 T1 = 150 T2 = 150 Tshift = 0 Trg = maximum T1 = 1 T2 = 1 Tshift = 0 Trg = 2 Trg = min Pick a number ANYWHERE inbetween T1 = 50%*Trg to the ground Torsen 75/25/25/75 BR = 3:1 T1 = 225 T2 = 75 OR T1 = 75 T2 = 225 Tshift = 150 Trg = max T1 = 1 T2 = 3 OR T2 =1 T1 = 3 Tshift = 3 Trg = min In straight line acceleration that is advantage Torsen. PER my own posts. Turn, that changes things. Why? Because you shift torque in a torsen car, specific to the 300lb/ft car, 150 lb/ft of it. In a locker, you never shift any. The Trg reduces, and the car understeers with the same torque all the way thru the turn. You lift a wheel, total torque to the ground reduces 50% f/r in relation to each other. A Torsen OTOH, can sense driveshaft rotation slowing in relation to the front, and transmit 100% Tshift to the other axle given the right circumstances with NO loss of actual traction. So Trg is max, traction is max, but Tshift is max as well. What is that point? I don't know, I know this, it's there, it has to be. 90 degrees of slip with NO power is a STOPPED rear wheel. 90+ degrees is a reverse rotating wheel. What's the difference? Torque. So, AT a given cf, with a given slip angle, the torsen will transfer maximum Tshift while accelerating. When you go on the gas, and the rear driveshaft rotates faster than the front (not a traction problem), you transfer Tshift max to the front. Until a tire breaks free, you haven't decreased Trg to the ground. I also argue that the slip angle needs to be NO where near 90 degrees for this to happen, btst. I am frustrated by this discussion. Why? Jeff and I have not argued anything, just presented physics. And we aren't saying that torsen is a bad thing, and it's a GREAT thing in terms of absolute traction in a straight line. We've experienced it's dark side, and we haven't mastered all the variables of it yet. I'm not convinced we will. However, reiterating math, is silly to me, it's in the paper presented. Dave, you need to understand what the difference is between wheel lift and slip angle, in relation to a center diff vs a fwd/rwd diff. You need to understand what the difference is between Trg max, and Trg min, in relation to traction on a locker. In a center diff, BR isn't necessarily traction, it CAN be slip angle. In a locked diff BR is the same always, the only thing that will change that absolute traction, but that change reduces overall Trg only. Why? Cuz you can't shift the torque split. You only reduce Trg to the ground. When a locker goes to the same slip angle, 150 goes front 150 goes rear, all the way thru the turn. Or a wheel loses traction and the T1 + T2 = %*Trg. But power, in terms of absolute torque to the f and r traction is a CONSTANT. With a torsen, that is not true anymore. Why? Because torque CAN BE in relation to driveshaft rotation ONLY, not necessarily traction. It CAN be in relation to traction, my only argument has always been it doesn' t HAVE to be. By the definition of a center Torsen of "traction". Slip angle on a locker is a constant, on a variable split, slip angle becomes a variable, to the operation of a torsen. IN absolute terms of traction and torque slip angle is a traction issue. In reality that is exactly NOT what is happening, yet torsen is correcting for that exact non traction event. I'm not sure it can be made more clear, my hardrive is begging for relief..... Scott

**Follow-Ups**:**Re: cf***From:*Orin Eman <orin@wolfenet.com>

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