Re: alignments and the freinds who love them

[JustaxPHX@aol.com]

> > The goal is to have 0 degrees of toe when the car in moving in its most
>  > nominal condition.  This is usually at speed, straight ahead.  There is 
>  > some flex in the steering and adjustment system, so that under forward 
motion,
>  > things flex back, or out, a bit.  This is why a correct alignment has 
toe 
>  > in of a few degrees, to pre-load the system so it is a 0 degrees toe 
when it 
>  > is moving.

I was going to keep my two cents to myself but the above statement isn't 
universally correct ... for a start, it obviously makes a difference whether 
the car's front wheels are driven or not; likewise, it also matters whether 
the steering arms are located in front of the wheel hub or behind it.  Heck, 
even their location on the strut (high or low) will have an affect on how 
much static toe -- in or out -- is needed or desired.

As much as any other part of the car, the manufacturer's alignment specs are 
a compromise.  If you know what you're doing, you can optimize performance in 
some respects (turn-in, for instance) at the expense of others (tire wear, 
etc.); if you don't, you can make a real mess of things.  You must consider 
toe as only one factor in a complicated equation and be aware that not all 
cars are designed around the idea that dynamic toe should always tend toward 
zero...

That said, back to Phil's original question: Yes, a screwed-up alignment can 
make the car handle *very* unpredictably, especially in low cf conditions.  
However, the alignment specs for most Audis are pretty similar, mostly 
because their suspension systems are also very similar.

JG