Originally Posted by airborneranger
With a center diff can you keep a consistent power transfer ratio between the front and rear? Or does it change as the load changes between the front and back?
No. It only changes output ratio front to rear when the Front comes off the ground it sends extra power there (bad), when the front slips it sends extra power there (bad), or when the car turns it keeps the drivetrain from binding (good). Play with the diffs on your car now. pretend one wheel is the front axle and the other is the rear axle. Center diff works the same. Both output speeds of the diff average out to the input (ring gear) of the diff.
If you wanted to adjust how much power goes where you would need a viscous differential. It is a hydraulic coupler like a torque convertor. The output end of the coupler sends less power to the output end than the input. (it slips when a certain torque level is reached.)
A Lambo uses a VD, so did junky old Explorers. Maybe Porshe to?
You woud run the vd so the input side is on the rear. Rear is mechnically conected, no slip 100% spin. (The input side of a viscous diff has no diff action and is fixed to the carrier) The output side goes to the front drive shaft and slips some.....say 80% torque. The slippage causes heat and frictional loss. Bad for fuel economy.
That would give you 60/40 split. Kinda.