RE: Wheel rate v. spring rate (was 17" wheels on an Ur-Q)...

[JustaxPHX@aol.com]

>and also increases the unsprung weight by a not-insignificant number of kgs
in each corner.

... and your point is?  Every decision that's made about how a car should be
equipped -- be it by the factory's engineers before it's put into production
or at a later date by the car's owner -- involves weighing various trade-offs.
My decision to run 17" wheel-and-tire combos on my two cars is no exception
and was made with full knowledge that there was a price to be paid for the
additional benefits they offered.  Better transient response, for one, and
room for bigger brakes, among others... 

>discussing this with an old rally buddy of mine who was talking to the guy
who recently won the regional rally in his wrc->spec subaru.  he was
discussing the pedant for uprating wheels and tyres on subaru's.  "if i had my
way they would sell >them with anything but 15" wheels.  handle much better
that way."
>
>makes you think.

Actually, what makes *me* think is whether Audi originally designed the Ur-Q's
suspension around 205/60-15 tires on a 6x15 wheel or 215/50-15 tires on an
8x15 wheel.  So far as I can tell, the suspension geometry wasn't changed
much, if at all, to compensate for the change and given the difference in
diameter between the two, they both can't be correct.  Is anyone else puzzled
about this like I am or privvy to the logic behind Audi's decision?  Perhaps
it was just one of those "happy accidents" that worked out far better than
anyone thought?