Quote Originally Posted by sodaz View Post
What about tyre weights? Which tyres are lighter than others? The 17" rims are about 10kg in weight (about 1kg more than the 16") so I want to make sure that the tyres I put on aren't too heavy. They look awesome compared to the 16" rims. Can't wait to put them on. They should increase overall grip a lot.

Will it still be ok for me to use the 16" space saver spare? The overall diameter will increase 0.54cm according to my calculations - From 205/55/16R to 225/45/17R.
You need to check with each tyre manufacturer about tyre weight. There is a huge variance across the brands and many do not publish that info anyway.

And yes you can still use the space saver but the car will probably not track straight due to the difference.