I've been looking at second hand winter wheel packages and would like to know if you guys think I can get away with tucking 225/60R17's under the fenders?

Diameter will be bigger by 1.6" - do you think this amount will be significantly too big?
http://www.miata.net/garage/tirecalc.html

I'd appreciate any advice.

 

I actually just tried to fit a set of 245/50/18 Dunlop M3's, which are 1.7" taller than stock, under my fenders. I mounted one up, pulled the spring and cycled through the suspension. At ride height, it just barely rubbed the front of the front fender liner when turning (not a huge deal), and in about the last 2 inches of jounce it was touching the fender lip (actually kind of a big problem). It was impossible to turn the wheel more than about a half-turn at that point without crunching the fender. I didn't even check the rear because I wasn't about to run massively different diameter tires front and rear. Lucky for me, I got the tires dirt cheap, and I have a tire mounting machine at my disposal, so the cost of this test was minimal.

As far as I can tell, nobody has tried to run tires significantly larger than stock, as evidenced by my thread about 225/60/18's (2.8" taller!) a couple weeks ago, and from my own testing, I don't think anyone should without lifting the car a bit. Which can't really happen without overtravelling the front lower control arm's rear spherical joint.

Hope this helps.

 

Hey Ken.

I hated you for selling your snowtires to someone else but now I appreciate you telling me that the larger tire diameter won't work! LOL

Thanks for your help.... I guess 1.6" is a lot more that I expected it to be....

 

Yeah...sorry about that. I was so excited about running big trucky tires on my 8 and so disappointed to find that I couldn't. I'm glad that my work has been useful to somebody else.

 

So what would you say is the tallest tire you could run? Would a 1' taller tire fit?

 

I don't think you could go up much more than 1/2" if even that. While I had the spring off, I also cycled through the suspension travel with my 25.7" diameter 245/40 tire, and the clearances were ridiculously tight. I didn't realize how big of a difference an inch is until I stacked all my different diameter tires next to each other. In the picture, there's a 225/40 (25.1") up front, the stock 225/45 (25.9") in the middle and the gargantuan 245/50 (27.7") in the back. Even the .8" between the two smaller tires is a pretty big difference.