Quote:
Originally Posted by sperry
Nope.
It's not a transfer case, nor does it act like one. At full lock, you may not have a speed differential between the front and rear wheels, but there is more torque at the rear due to the gearing in the diff. On dry pavement, with tons of traction, in a straight line, at 100% lock, the wheelspeeds will be the same, but the rears are pushing the car harder than the fronts are.
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Well, you are close. At 0% lock is when the gears are in effect and the torque is distributed via the gear ratio, so with tons of traction, in a straight line the rears are pushing harder than the fronts. And, if I understand the drawing correctly the clutches completely lock out the gears. So then in the same situation when we 100% lock the diff, the gears are taken out of the equation and we have 50/50 torque to the front and rear. I'll draw a load path on the cross section tomorrow. I promise.
Quote:
Originally Posted by sperry
With the front wheels off the ground, there is zero torque on the them because there's no ground pushing back as they turn, but the rears are not getting 100% of the engine's torque... they're getting 65%, the max allowed by the center diff. The rest of the power is being wasted spinning the front wheels. Similarly, with the rears in the air, the fronts can get only 35% of the engine's power, even though they're generating 100% of the torque that's reaching the ground, since the rears are spinning freely.
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Again, if I understand the drawing correctly, this is not the case -- the clutches lock the input with the two outputs. So then with either axle off of the ground the axle still on the groung would _have_ to get 100% of the torque -- there would be no where else it could go.
I'll try to get a drawing done of this thing. It should explain everything. I am not sure at this point, but this looks very similar to something I have worked with before.
Quote:
Originally Posted by sperry
It's the difference between the torque split of the differential, and the effective torque reaching the wheels. Sure there are situations where the torque at the wheels vary greatly from 100%/0% to 0%/100%, but never is the torque passing through the diff split any other why than 35%/65%. To put it another way, the torque distribution may be 100/0, but that means the torque getting to the ground is only 35% of what the motor's generating. Which is exactly why you don't want an AWD car lifting wheels, doing so wastes power in the differentials ...which brings us full circle to what started this thread.
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