225/50/16 tires on A4?

[quk@sievers.com (Phil Payne)]

In message <c=US%a=_%p=Software_Metrics%l=SYNCRO-970304125518Z-148@syncro.metrics.com> Tom Haapanen writes:

> And a 10% wider tire will *not* give you significantly more grip, let
> alone 10%.  The contact patch remains essentially the same size, just a
> different shape, and the sidewalls (whose flex is a major factor in
> handling) are still the same height.

True.  Even if the area increases, the loading per unit of area decreases and 
the product of the total loading and coefficient of friction remains the same.  
Wide tyres when slip has _started_, but not really until.

> Not to mention that if you are planning to drive these in the not-so-dry
> conditions, the wider tire will give you more aquaplaning potential in
> the wet, and worse traction in the snow.

There is a very specific and strict warning about aquaplaning in the 1988 
ur-quattro driver's handbook.  I know of at least two cars having been lost 
because of it.

Another factor is aerodynamic drag.

--
 Phil Payne
 phil@sievers.com
 Committee Member, UK Audi [ur-]quattro Owners Club