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Re: torsen tech 102



> >thats it folks.  pretty simple really.  a nice little device.  does the
> >torsen get confused by slip angle differences?  no it can't any more than
> >the locker can.  because it doesn't see them.  the torsen and the locker
> are
> >identical in behaviour during cornering because they are both locked and
> >allow no axle speed differences.  in both cases torque will go to where
> >relative wheel slip dictates that it should go.  once the bias ratio is
> >reached (and about when the locker goes into terminal understeer), the
> >torsen will limit understeer by diverting torque to the front (i.e.
> allowing
> >axle speed differences).  it is at this point seeking to deny wheel spin on
> >either axle.

> What you have just described here is a behavior of the torsen to send
> the bias ratio of torque to the rear of the car which sets up an oversteer
> condition and then once the bias ratio is reached to divert torque to the 
> front which sets up an understeer condition.

...only if the rear can't handle 75% and starts slipping will torque
go back up front, more specifically, if the inside rear can't handle
37.5%.  Now the condition being discussed (bite) is where the
torque got thrown back due to the rear wheels turning slower.

Consider this... if the rears do start to slip, we get major oversteer,
but it will take a little time before they catch up to the fronts
at which time torque will start moving forwards and we go back to
understeer.

So, rears break loose - major oversteer - car pointing at apex.
Rears catch up to fronts - torque goes forwards - understeer.

It was the timing that was confusing to me.  The torsen essentially
acts instantaneously... _unless_ the wheel that was turning
more slowly has broken loose and is spinning up in which case
it continues to receive the 75% until it catches up with the other
axle.

Orin.