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RE: The Definition of Spider Bite (tm -SJ) in a Torsen Center Diff

Dave E writes:
>oh yes, the "definition of the bite".  which you have failed to come up
>with.  care to divvy up this time????

Dave, let me predicate this post with a toast to you for your research.  
Based on it, me and several others on this list, feel this discussion is 
going forward (mit nein turns:).  Appreciate you taking the time to put the 
homework effort into the discussion, and since we are really close, IMO, I 
will stick only to the points you raise, with as little phlogistic tangents 
as possible.

That said, I have put forth a bunch of definitions and scenarios in the 
archives, and Jeff has also.  My claim has always been in terms of chassis 
dynamics, extending torsen torque shift to the chassis dynamics in a turn.  

To summarize:  A torsen center diff chassis, in a turn, *can* suddenly and 
without prediction, shift from an oversteer to an understeer to an oversteer 
(ad infinitum) condition in a single turn.  This phenomenon I refer to as The 
Spider Bite (tm -sj) and is a nature of the torsen center differential.  This 
creates a 'challenge' in controlling a center torsen vehicle in a high 
performance - high cf environment or a low performance - low cf environment.  
I come to this conclusion based on my research into how a torsen differential 

Definition of Spider Bite (as I understand the device, based on my research 
and Dave E's):
Torsen center diff car enters a given turn, turning radius fools torsen into 
allocating torque rearward -O-, which (depending on all the variables in 
885140) *can* overload the rear tractive ability, which then changes the 
variable affecting torque shift from a slip angle one (turning radius) to a 
tractive variable (traction at the rear wheels), which per 885140, is 
"independent of the forced slip resulting from the vehicles circular path", 
and this shifts torque forward, causing -U-. which then *can* regain tractive 
force rear, which results in -O-, because once tractive force rear is 
regained, torque shifts rearward due to turning radius.  This scenario *can* 
cycle several times in a single turn.

This assumes all variables the same as 885140 except accleration(Trg)=cf 
(they are the same variable for all intents and purposes).  Changing *any* 
variable, *can* increase or decrease the chances of Bite, but can't eliminate 

Single yes/no question Dave (/others):  Looking at the above scenario v your 
research, isn't the definition of bite as I presented above, possible (I 
didn't ask: *likely*)?  After the answer, you(/others) are welcome to address 
the errors of my thinking.


Scott Justusson