Both these tires should work on a 2000 4.2? I've talked to quite a few shops and have had conflicting answers. Some people said I should stick to the stock size and not alter the ratio. An other guy said it would throw out the computer....Another said it would throw out the speedo. I need a affordable winter and can get a good deal on a set of 225/45/17's. From my understanding these tires aspect ration are close. What do you tire Guru's think?

Check this site out http://www.miata.net/garage/tirecalc.html it shows how your speedo will be affected.
If its a good deal and you can get good snows...I say do it.

I also forgot to ask if the stock A6 4.2 17" wheel will take a 225, or is this tire to narrow? Thx

E-mail Gary@tirerack.com and ask hm the question.

a good speed/ odometer reading calc on this link

http://images.google.co.uk/imgres?im...l%3Den%26lr%3D