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Re: More bytes on bites
In a message dated 98-03-01 19:58:47 EST, you write:
STOP RIGHT HERE. TORQUE != HORSEPOWER.
Horsepower is proportional to torque * RPM. The following would
ONLY be true if the two shafts are rotating at the same speed,
and that doesn't seem to be the situation being discussed.
> T1 = 168.75
> T2 = 56.25
> T1 = 56.25
> T2 = 168.75
> Tshift = 112.50
It's exactly true if the two shafts are rotating at a DIFFERENT speed Orin.
Think of it this way. When the slip angle gets high enough, the Trg (Torque
at the ring gear) = Engine Torque/HP (here you can insert 225 lb/ft just as
easily), that means the rear is SLOWER turning than the front. Why? Because
at a high enough slip angle, the rears will slow in relation to the fronts
(nothing to do with torque, all to do with slip angle and track), but the
Torsen is a dumb device, and will send maximum designed torque split from the
ring gear to that slower spinning axle. For the exact reason you state above,
it's design is to apportion more torque to the slower spinning axle, to make
them spin at the same speed. Now, understand that unlike a rwd or fwd torsen,
slip angle on a center torsen may be happening for the exact WRONG reason
(slipping wheels in this case slows rotation of the rear axle), so the
diminishing or equalizing torque that rwd and fwd might enjoy (specifically,
total collective torque reduces), doesn't necessarily happen in the center
torsens. Why? Because the slip angle makes the torsen think that the REAR
has more traction than the front, which is EXACTLY not the case. Torque
sensing means torque to one axle is higher than the other at any given rpm.
The torsen tries to make the shafts go the same speed, which is exactly HOW
you get the problem above.