Re: new t*rs*n paper (no flames)

[Dave Eaton <dave.eaton@minedu.govt.nz>]

sorry jeff, perhaps you don't understand what i am saying...

1) the paper identifies that chassis dimensions and characteristics are vital
in the selection of a torsen bias ratio for a centre diff.  as is the engine
torque characteristic.

2) audi did not change the torsen (same part number) between the type 44 and
the ur-quattro, for example.

3) the chassis changed, significantly.

4) therefore (given statement 1) we would therefore expect different torsen
behaviour between the different chassis.  i believe that this is what we are
seeing.  for instance, i have never driven a type 44, but i would expect to
find it very different from either of my cars, due to audi's design decisions
about performance, roll stiffness, comfort etc.  all these affect the
performance of the torsen in a centre diff application, according to the paper.

i'll try and get the sucker scanned over the week-end...

hth,
dave
'95 rs2
'90 ur-q

>>but thats the whole point.  the torsen didn't change between the (eg. ur-q
and
>>type 44) models, but everything else did (wheel base, track width, centre of
>>gravity, roll stiffness, etc), leading to the different behaviour identified
>>above.
>
>Needless to say, I disagree ... how do you take a statement that says, in
>essence, "The ideal bias ratio will vary depending upon a lot of different
>factors" and conclude from it that the "spider bite" phenomenon is the
>result of differences in "chassis dynamics" among the various Audi models?
>One doesn't necessarily imply the other...
>
>In fact, if anything, I'd suggest the reverse: to wit, differences in
>"chassis dynamics" -- you're aware this terminology is being misused, right?
>-- might mask or at possibly mitigate the effects of a less than optimal
>choice of bias ratio.
>
[snip]
>    _                _
>   / |      _| o    | \       _| o  Jeffrey Goggin
>  /__| | | / | | __ |  | | | / | |  audidudi@mindspring.com
> /   | |_| \_| |    |_/  |_| \_| |  http://www.mindspring.com/~audidudi/
>________________________________________________________________________