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re: alignments and the freinds who love

Phil Rose wrote:
>Can anyone offer a well-informed opinion as to whether alignment of a '91
>200q to the wrong specs (what specs, who knows?   '92 100q? the S4?) is
>likely to induce significant (and disasterously negative) alteration in its
>handling. I'm sure to be seen as grasping at straws here, but I think it's
>an important issue to try to clarify. Alignment is casually regarded by
>many as an issue of merely tire-wear and straightahead tracking. That's
>obviously wrong, but _how_ wrong is it?

Hi Phil, let me offer you an Un-informed opinion (semi-informed?).  As
you know, I'm not an engineer, but I've played around with different
alignment settings on different cars.  I find it makes a HUGE difference
in the feel of cars, especially with snow tires.  For what it's worth, in my
experience, the rear toe setting is crucial for oversteer/understeer.  If
your guy got that one wrong it could easily send you into the weeds.
The balance between rear toe and front toe also dramatically affects
the feel of the car. Front toe is very easy to detect, and the first thing
that I notice when it has been changed.  It shows up especially when
entering corners, and overall steering "responsiveness."  For instance,
I've found on my miata that a little bit of toe OUT gives very rapid turn-in,
which is nice at the autocross, especially when coupled with a bit of
toe-IN at the rear.  But it makes the thing unstable on the highway (darts
all over).  A bit of toe-in at both ends makes the thing feel much more
stable.  Oh yeah, the tie rods on older Audis are always frozen up
in my experience, so a lot of alignment guys check and if they're at
all close just leave 'em (or even if they're not close).

I've got less experience with things I pay other people to set for me.
For instance, camber settings I can recognize in higher cornering
speeds (the tire is more upright around corners, but leans in at the
top in a straight line).  I had an old Porsche Speedster (swing axles)
where big amounts of negative camber was simple self-preservation
to keep the car from swapping ends unexpectedly.  Of course it
constantly wore out the inside edges of its tires as a consequence.

And as for caster, all I know is that it affects the self-centering of the
wheels, so when it's reduced the car doesn't "track" as well.  I find I'm
pretty insensitive to the way it feels.

As for your question of differences in specs, I don't believe the my
S4 is much different in specs than your 200, but I've never had a 200
so I am probably way wrong.

HTH!  A subjective answer & I'm sure you'll get better responses
from those who know more than I

Doug Haley
'92 Ur-S4
'99 A4 1.8tqms