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Re: Physics is interesting

In a message dated 98-03-09 15:04:58 EST, you write:

<<  Nowhere did relative speed come into the picture.
> Seems to me that if there is any speed differential at all,
 >then torque split will be at max with the slower turning
 >shaft getting the greatest torque, or put another way,
 >torsen resists speed differential up to the point of max
 >torque split at the output shafts, at which point, the
 >shafts slip relative to each other, still at max torque split.
> Given this, I think we can remove any quantitative treatment of
> speed differential and say if there is any speed differential,
> max torque is going to the slower turning shaft.
For KISS I would tend to agree.  I think where a lot of folks might miss my
reference to "spinning" is that, I argue, you can have the rear tires spinning
with tshift max at the rear.  So, I don't totally agree that there can be no
speed differential, in fact there can be with Slip Angle in the equation.  My
point to help some that may not understand Slip Angle in relation to Traction.
The rear can't spin 'faster' than the front without some "tshift" however,
with enough slip angle, you can be spinning tires in the back with NO tshift
at all.

We must also understand, that tshift Forward only has to be to 50/50 to get
understeer, not tshift max.  Remember, the whole discussion stemmed from the
fact that a Torsen makes for understeer, oversteer, understeer all in one
corner.  Power up is an oversteer condition, a 50/50 split is understeer.  So,
in actuality, we can have Tshift max rear (300lb/ft 78/22/22/78 Torsen) of
234r/66f (Oversteer), and have Tshift forward of only 84 (150f/150r) to have
Understeer in the same corner.   We could argue too, that with a proper
chassis setup, you could have a Tshift of 2lb/ft to go from understeer to
oversteer.  I hardly think this applies to this discussion, but it sure could.
Makes ya wonder what the "other" side of that 57/43 S4 torsen is though.

> This would be what those weasel paragraphs at the end of the paper
> would be refering to.  (I read the cornering paragraphs as
 >'It ain't so great when cornering'.) >>

Scott Justusson