Car: 2009 EXGT auto, Audi TT 190
Join Date: 26th May 2007
Thanked 110 Times in 104 Posts
Given 2 wheels the same width, appropriate width spacers used with an 8 gen wheel fitted to 9 gen car would position the wheel similarly to that of the original wheel.
Of course should the 8 gen wheels be wider for example, then without spacers the position of the outside of the wheel may finish under the arch as the original.
(as well as pcd's and et's and spacers, there's always the question to consider will the inside of the wheel foul/contact any part of the car/ suspension/brake part etc, and of course the wheel mounting bolts lengths/mounting face profile)