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RE: spider bite
errr, au contraire scott, there is considerable documentation which directly
contradicts your view, from a variety of sources. for example:
i have a white paper from zexel which specifically mentions a range of
chassis factors in the behaviour of the diff. let me quote:
"The ideal centre differential Torque Bias Ratio layout in the 4 operating
modes is a function of vehicle dimensions (wheel base, track width, centre
of gravity height, etc.), suspension elasto-kinematic design (stiffness
front/rear, angular variations, etc) and engine torque characteristics for
given road conditions. Therefore the ideal design characteristics for a
centre differential can be determined after a great deal of subjective
vehicle tests. The optimisation will be a compromise between different
set-ups, depending on the surface conditions (dry asphalt, wet asphalt,
snow, ice, etc)."
i think that the text makes it pretty clear, don't you?
i also have a white paper from the boys at gmc who developed a mathematical
model for the torsen with 6 (count 'em thats six) degrees of freedom.
in your model scott, you've got 1 degree of freedom (i.e. if there's a
torsen, there a bite).
enough said. as for your previous attempt to recreate history by stating
that phil or myself had categorically denied the possibility of ill-defined
chassis behaviour with the type 44 at the limit, i am endeavouring to take a
'88 mb 2.3-16
Date: Mon, 20 Sep 1999 08:52:55 EDT
Subject: Re: Spider Bite
In a message dated 9/20/99 7:40:54 AM Central Daylight Time,
> > Oh contrair piere, er, Eric. Up to today, he ALWAYS denied that it
> I don't believe so, and I don't believe I've changed my tune at all.
> If anything - quite the contrary. What I felt in the Type 44 is
> something utterly new to me, and it superficially resembles your
> description of spider bite. Now I know that there is something there, I
> shall attempt to explore it in future sessions.
> I've never had this experience in a Type 85, and as several listers will
> confirm four-wheel drifts and controlled understeer are a regular
> feature of my day-to-day driving. I've done over 110,000 miles in the
> car, and never felt anything like this.
> So I'm still strongly at variance with your contention that this
> behaviour is inevitable with a Torsen centre differential. Maybe the
> Torsen contributes to it or even causes it on the Type 44, but I've
> never felt such behaviour from a Type 85 - not even remotely.
Bottom Line: There is no documentation to support the argument that
wheelbase, suspension, or chassis dynamics "corrects" spider bite, and you
have posted and described EXACTLY the same characteristics I have found in
ALL torsen center chassis I've driven (and that would be all of the torsen
wheelbase applications). Without question, the 44 chassis has a larger
weight shift, so the potential is higher to identify it. Given the right
of circumstances, ANY torsen can exibit the same behavior, btdt. IF the
device is in all the chassis...
Look forward to your reports on the 44. When you find it in the 85, I
you will post it as well.