« Reply #13 on: 26 March 2017, 14:30 »
It's not so much the space saver being an 18" wheel, that's just to clear the brake callipers and allow for a small skinny tyre to be fitted to it and the same size spare will be fitted to most of the range I'd guess for simplicity of manufacture.
The rolling circumference is the most critical factor Brendan and as Joe says, even a 17" wheel will clear the calliper and is a popular winter wheel size.
It's the tyre dimensions that will upset the 4-motion if they're not similar to the ones fitted to the other corners it'll constantly think you've got a flat tyre plus the vehicle will be listing to one side!
225/45/17, 225/40/18 and 235/35/19 all have a reasonably similar rolling circumference so won't upset the electronics too much, plus the tyre fitted will be of a suitable speed rating unlike the skinny space saver.
Logged
‘25 8.5R, ‘23 8R, ‘20 8CS, ‘19 135iX, ‘19 TCR, ‘17 Ed40, ‘17 GTD, ‘15 7R, ‘13 GTI PP, ‘11 GTI, ‘09 GTI, ‘98 Ibiza Cupra, ‘05 GTI, ‘06 Polo GTI, ‘04 GT TDI, ‘05 Fabia vRS, ‘02 GTI T, ‘03 Ibiza TDI 130, ‘01 Leon 180, ‘89 mk2 16v, ‘99 Ibiza TDI, ‘96 VR6, ‘98 Ibiza TDI, ‘92 VR6, ‘88 mk2 8v, ‘92 Polo G40, ‘91 mk2 8v, ‘89 mk2 8v, 205 GTI 1.9, ‘83 mk1 GTI, ‘80 Scirocco GTI, plus some others I’ve forgotten
