Interesting item on AOL [Tires]

[jason@scirocco.org (Jason)]

At 10:05 PM 3/13/2003, DieingSwan@aol.com wrote:
>. Could someone describe to me the philosophy behind the
>recent popularity of BIG HUGE rims and LITTLE SKINNY tires? Is there any
>functional benefit whatsoever?

Absolutely.

By "skinny" I assume you mean tires with small sidewalls, not skinny widths...
A larger wheel will require a smaller sidewall to retain the same overall 
diameter that the car was originally sold with.  Retaining that diameter is 
important because the car's suspension (and indeed entire driveline) was 
designed around that size, and to a lesser extent, your speedometer (and 
odometer) will remain accurate.

A "Plus-size" wheel and tire combination (meaning a larger wheel with 
appropriately reduced sidewall height on the tire) will generally offer a 
higher level of overall grip, better braking, and better traction under 
power.  It will also offer enormous benefits in transitory responses and 
turn-in by reducing sidewall flex.

The drawback is, among other things, are a coarser ride.  And, with 
anything, there is a limit.  Putting 18s on a Scirocco with 205/20-18s (or 
whatever other fictional tire size would fit right) would probably offer no 
handling benefit over the appropriate sized 16s.

17s on an A3 chassis is a little much - ask me, I know... I have 205/40-17s 
on my VR6.  My personal opinion that the ideal wheel size for best handling 
is 15"s on the A1 and A2 chassis cars (195/50-15), and 16"s on the A3 
chassis cars (205/45-16).  But I have to say, my 17s look fantastic on the 
Golf. :)

http://www.parts4vws.com/registry/registry_detail.asp?MemberCarID=3878

Jason

And PS:  That is a Neuspeed intake on the eBay car...