As stated above will a set of 17x8 et35 5x100 fit my 9n3 at the minute it's running 16x7 and is lowered 40mm all round (don't want the wheels to stick put realy far with them being 8" wide ??

Comparing the 8x17 ET35 wheels to Factory-issue wheels fitted to the Polo, you get the following results...

5x14 ET35 - the 8x17 ET35 will be 38mm closer to the suspension, as well as being 38mm wider on the outside.

6x14 ET43 and 6x15 ET43 - the 8x17 ET35 will be 17mm closer to the suspension, as well as being 33mm wider on the outside.

6.5x16 ET38 - the 8x17 ET35 will be 16mm closer to the suspension, as well as being 22mm wider on the outside.

6.5x16 ET43 - the 8x17 ET35 will be 11mm closer to the suspension, as well as being 27mm wider on the outside.

As you don't give the offset of your current 7x16's I can't put them into the equation for you - but you can calculate them yourself on http://www.1010tires.com/wheeloffsetcalculator.asp when you know the offset.

HTH