Just went on tirerack and found the 18" rim info for the sport package. Here is the info. Offset: +35
Backspacing: 5.94"
Bolt Pattern: 5-114
Rec. Tire size: 225/50-18
Now I can finally go get some tires and rims and prepare the Z for winter. By the way my 2010 Z should be in next month
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