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Re: Allignment for all 5ktq owners - some helpful hints

In a message dated 97-01-12 04:48:06 EST, you write:
> How much should a normally crowned road affect the tracking and wheel   
> center position of an '87 5000CS Quattro?  I am having it alligned right   
> now, and when I drive it out of there I just want to make sure I get my   
> $80.00 worth.  I know I paid too much...  How much should it wander   
> within the worn tracks of the highway?  I run 215/60-15 Dunlop D60A2's   
> with less than 3000 miles on them @ 35lbs of pressure.
> Robert Dupree
> '87 5000CS Quattro  

            I had to respond to this one as I have the same car and 
the same tires with about 15K on them at 38Psi.  My  car will track pretty 
straight on most roads-especially the highway. But get it on a 
crowned road or one with tire ruts and the car pulls a little left. 
Don't know why left but the alignment guys have assured me that 
everything is within spec and I've replaced all worn suspension parts 
that could cause it to do this. It's not bad at all but the wheel 
position will cock to the left just a little. No abnormal tire wear 
whatsoever. I figure the crowned roads here explain everything. 
Coupla things:
 *  Replace the sway bar bushings there are 6@50.00USD, the control arm is
triangulated with a swaybar with rubber bushings, hardly the design of
choice, best to optimize it...  Chances are this is the problem but.....
*  Make sure your camber is set at .5 negative degrees at all four, that is
the best for this chassis....  A lot of "kits" (in fact all of them) don't
allow this at the front, best bet is to take the worst and copy that on the
other 3.  Example, kit suspension, got .5 neg on lf, only could get 1.5neg on
other side (lowering car decreases positive camber ability), went with the
1.5...  Not great for tire wear, but car corners great....
*  I know most run high pressures on the D60A's, however, 32f/33r on a high
performance tire with that chassis is fine, at least try it....  Altho the
weight would dictate the reverse, I found a little better turn in with the
higher rear...
*  RAKE ANGLE....  Don't know if you've done suspension mods, but rake angle
is key
    * Substraight on this - be very "aware" of suspensions that have
combination of hydraulic shocks and Gas  
      Pressure combinations, they actually change rake angle based on temps
(Gas expands as ambient temps
      changing ride height, Hydraulics change visosity but not ride height
any significant amount), a no-no in my book.... 
      Regardless, your rake angle is the key to proper suspension control,
I've posted before that a 1/4inch change can
      really change the handling characteristics of your car, it's that front
chapman, rear multilink thing again...
*  Subframe alignment specification, specifically engine/trans alignment
spec...  Check it, especially if you've done a clutch, moving that
engine/trans out of that spec affects f/r balance...  It's in Bentley
*  Those large rear bushings, been replaced?   A LOT of potential play in the
back end if those are whacked
*  Make sure your alignment guy could move the tie rods, 5k's tend to lockup
all the time, it's a heat and destroy mission to get them off....  A lot of
guys just figgr it's close enough to spec and leave it alone...
*  Lower control arm bushing is key
*  Upper strut bushing camber plate....

*  BUSHING INSPECTION... 9 times out of 10 the easiest way to tell if a
bushing is shot is to inspect the rubber to metal sleeve bond (outer and/or
inner <pressed), there should be a solid bond there....   If you notice
cracks or splits between the metal and the rubber, replace