Part of it is tire diameter, part of it is (m) (archive)

My 235/45's are only 1/4" taller in diameter, but I think with the combination of a slightly taller tire, and the "non-stock" wheels the wrong part of the tire is in the wrong spot inside the wheel well, and I get rubbing. If a 245/40 slick Hoosier gets rubbing, then I would imagine that any other would as well. There is also the fact that it just looks plain old crazy. 245mm equates to 9.65" wide. Which is a full 2 inches wider then the strock wheel, thats crazy. Now I realize that the rear wheels have 245's on them, and they look too small, so the 245 is not an exact indication of how wide the tire is, but it is most definitely wider then the wheel.

235/40 in front, possibly 45 if you are willing to take the risk, and 255/40 in the rear. SInce you have a HUGE drop in the height of the rear I would think it would be good to get the rake a little more front-heavy. Get the nose dropped down a bit with ethe 235/40's, and get that back propped up just a hair with the 255's.

Just My opinion (from spending TOO many hours doing the whole tire comparison dilemma)

Based on the website

http://www.powerdog.com/tiresize.cgi

This is what comes up

Stock Tire 225/45/17

Sidewall = 4.0 in
Radius = 12.5 in
Diameter = 25.0 in
Circumference = 78.5 in

New Tire 245/40/17

Sidewall = 3.9 in
Radius = 12.4 in
Diameter = 24.7 in
Circumference = 77.6 in

So, this 245/40/17 tire actually has a slightly smaller sidewall height and just slightly smaller if not close to the stock 225/45/17, but 20 mm wider. That almost translates to an extra inch in width (25.4mm = 1 inch).

But as usual, what looks good on paper may not translate well into real life. I may be also forgetting some other factors.

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