Re: What's the big deal about Torsen?

[audidudi@delphi.com (Jeffrey J. Goggin)]

>Part of the difficulty of "what's better" on this list is that there are
>two distinct camps at work here: "Racers(and wannabees!)", and "daily
>drivers", both groups which appreciate the quattro for its excellence in
>technology (and whatever).

True enough ... good point.

>A conventional differential "favors" the output with the least path of
>resistance, hence when you remove the traction contact from one wheel,
>it is the only wheel that spins; no torque is applied to the other
>wheel(s).

Actually, the amount of torque delivered to the other, non-spinning wheel is
the same as that applied to the spinning/low-traction wheel ... since this
can be a very small amount, though, it just seems like no torque.

>For the racer/wannabee; When you "get on it" with a Torsen, you will
>have the lowest traction axle spinning faster than the other.  (Usually
>the rear)  You won't have this with a locked center.  From this
>perspective the control will not be as defined with a Torsen. (Yet
>control always has its limits)

The problem I've had with the Torsen is that under racing/high-performance
driving conditions, it behaves in a "schizophrenic" manner: At times, the
car behaves like it's FWD; at others, RWD, and there's no way to predict how
it's going to respond until it's too late ... learning how to "drive around"
this can help -- for a start, stay away from trail-braking! -- but a locked
center diff is probably a better solution if the speeds are high enough and
the corner radii large enough.  It doesn't work very well for autocrossing,
though ... BTDT.

I don't know if I'm the "racer" PDQSHIP referred to (I'm sort of on the
sidelines while my car's being built!) but I'm not quite ready to give up on
the Torsen just yet ... I suspect some of its quirks have to do with the
interaction between its characteristics and the design of the suspension,
which is basically the same for both Torsen and non-Torsen cars.  If so, it
may be possible to modify the suspension to be more sympathetic ... and then
again, it may not.  Of course, we are talking about racing here so none of
this is necessarily applicable to street cars and street usage ... as he
said, time will tell.    


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