Re: Handling the Rein

[Josh Pinkert <flush@us.net>]

At 08:46 AM 2/25/98 -0500, QSHIPQ@aol.com wrote:
>Dave Eaton writes, regarding Sarge's post:
>
>I believe you to be backwards.  Jeff G actually said he filmed this scenario.
>As you overcook a corner, you will find that the rears are hanging out, and
>the slip angle is so much that the rears slow, they are plowing sideways, not
>forward, more so than the fronts, since you have them on the inside of the
>turn and steering toward the drift.  So the rear axle is spinning slower than
>the front, on a torsen car, more torque will be transmitted to those slower
>spinning wheels.  Let off the gas, the torsen will now transmit less
torque to
>the rear axle (since letting off the gas is decreasing torque by definition)
>hunting back to a 50/50 split, which results in understeer, or if you went
too
>far already, the back end unloads, and you just got a spin from lift throttle
>oversteer.  Dave, take a look at your power tables for the Urq and the RS2.
>Apply those to your throttle position.  As you decrease output of the motor,
>"splitting torque F/R" really doesn't mean much.  You are really back to good
>'ole chassis dynamics.  And the torsen still hunts, upsetting those dynamics.
>You are talking about rwd oversteer to fwd understeer and/or lift throttle
>oversteer, all in the same car and turn.
>

This brings up another thought.  Does the torsen effect braking??  This may
be trivial, but this thread IS about exploring the dynamics of the
torsen...right?  If the above scenario is true...follow me through this.
1)  ABS disabled.  2)  Straight line braking approaching the threshold.  3)
 All 4 wheels turn at the same speed.  4)  Brake bias set up becomes import
here, because if one end locks before the other, the torsen will begin the
*hunt*.

What actions will the torsen take in the above situation?  I assume that
the locked wheels will appear to have traction.  Will the torsen have any
effect?


- Josh Pinkert
- Josh@Pinkert.com
- '98 A4q 2.8
- ISO '70-'73 Porsche 911