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RE: ur-quattro differences (continued)
>in summary therefore, it is clear that there was a change in track which
>occurred with the wishbone/balljoint replacement which occurred at the end
>of the '82 model year for the '83 year.
At the risk of playing the contrarian yet again, I will point out that unless
Audi redesigned the suspension geometry, the 21mm change in offset between the
6x15 and 8x15 wheels will automatically increase track width by 42mm. Given
the way in which the camber is adjusted by sliding the balljoints to-and-fro
at the end of the control arm, though, it's hard to pin this measurement down
too precisely and a few mm either way are probably irrelevant when there is
10mm worth of adjustment available at each side.
Had Audi wanted to keep the track width the same while using wider wheels and
tires, they could have done so; also, if Audi wanted to increase the track
width while using narrower wheels and tires, they could have done so as well.
That it appears they choose to use wider wheels and tires and let the track
width changes fall where they may again suggests (to me, anyway!) that the Ur-
Q's basic suspension geometry is the same for the early Series One cars and
later Series Two and Three cars.
>85-c-902-000, and the start of 85-d-900-001. in summary at the front, the
>changes involved new lower wishbone, ball joint, and new shock absorbers
>and anti-roll bar (along with their rubber mountings). there was a change
>in front springs at 85-e-900-324 (nov '83, during the '84 model year). at
>the rear the anti-roll bar was deleted and a new wishbones specified, tie
>rod, and the ball joints. the rear strut also changed for the '83 model
>year, along with the rear shocks changed and the coil springs.
And except for perhaps changing the amount of unwanted deflection in the
control arm bushings as well as moving the pickup points for the tie-rods when
the rear a/r bar was deleted, none of the changes detailed above will have any
effect upon the alignment of the wheel as it moves through its range of
suspension travel. To do this, at least one of the three pickup points
involved -- the center of the upper strut bearing, the axis upon which the
control arm's inner pivots rotate, and the center of rotation for the
balljoint -- must be relocated and in this case, we know they weren't (with
the possible exception of the 20v cars with the cast SS wishbones and three-
bolt balljoints; having never seen these parts first-hand, there's no way I
can tell for sure.)
The bottom-line is that changing a few minor details in part specs will have
no effect upon suspension geometry and by all accounts, it appears this is ALL
that Audi did when they upgraded the Ur-Q from 6x15 wheels with 205/60-15
tires to 8x15 wheels with 215/50-15 tires.
JG
>in summary therefore, it is clear that there was a change in track which
>occurred with the wishbone/balljoint replacement which occurred at the end
>of the '82 model year for the '83 year.
At the risk of playing the contrarian yet again, I will point out that unless
Audi redesigned the suspension geometry, the 21mm change in offset between the
6x15 and 8x15 wheels will automatically increase track width by 42mm. Given
the way in which the camber is adjusted by sliding the balljoints to-and-fro
at the end of the control arm, though, it's hard to pin this measurement down
too precisely and a few mm either way are probably irrelevant when there is
10mm worth of adjustment available at each side.
Had Audi wanted to keep the track width the same while using wider wheels and
tires, they could have done so; also, if Audi wanted to increase the track
width while using narrower wheels and tires, they could have done so as well.
That it appears they choose to use wider wheels and tires and let the track
width changes fall where they may again suggests (to me, anyway!) that the Ur-
Q's basic suspension geometry is the same for the early Series One cars and
later Series Two and Three cars.
>85-c-902-000, and the start of 85-d-900-001. in summary at the front, the
>changes involved new lower wishbone, ball joint, and new shock absorbers
>and anti-roll bar (along with their rubber mountings). there was a change
>in front springs at 85-e-900-324 (nov '83, during the '84 model year). at
>the rear the anti-roll bar was deleted and a new wishbones specified, tie
>rod, and the ball joints. the rear strut also changed for the '83 model
>year, along with the rear shocks changed and the coil springs.
And except for perhaps changing the amount of unwanted deflection in the
control arm bushings as well as moving the pickup points for the tie-rods when
the rear a/r bar was deleted, none of the changes detailed above will have any
effect upon the alignment of the wheel as it moves through its range of
suspension travel. To do this, at least one of the three pickup points
involved -- the center of the upper strut bearing, the axis upon which the
control arm's inner pivots rotate, and the center of rotation for the
balljoint -- must be relocated and in this case, we know they weren't (with
the possible exception of the 20v cars with the cast SS wishbones and three-
bolt balljoints; having never seen these parts first-hand, there's no way I
can tell for sure.)
The bottom-line is that changing a few minor details in part specs will have
no effect upon suspension geometry and by all accounts, it appears this is ALL
that Audi did when they upgraded the Ur-Q from 6x15 wheels with 205/60-15
tires to 8x15 wheels with 215/50-15 tires.
JG