I am confused about Plus Size Tire Sizing

[dev]

I have a 08 Touring edition Avalon. I noticed on : www.discounttiredirect.com that I can "0" size the tires. Not sure what that means. But I am looking to fill-up the wheel gap on my car and not ready to change from the stock wheels. Please help me understand this sizing options.

I like the way 235/55/17 looks but don't know if it will work?!?!?
Thanks, dev

www.discounttiredirect.com
Optional Tire Sizes
-Plus Zero
215/60-17
225/55-17
235/50-17
235/55-17
245/50-17

[boosted-fc3s]

"Plus 0" just means you are maintaining the stock rim size of 17" and going wider. Plus 1, would be an 18" tire, etc.

235/55 is almost an inch taller than stock. Its going to throw off your speedo about 2mph.

235/50 would be the proper width to sidewall ratio to go wider and maintain the same overall height. Whether you can stuff 235 width tires in the wheel well and on the stock rim is another story entirely.

http://www.miata.net/garage/tirecalc.html