what is the largest wheel/tyre that I can fit without modifications?
1010 tires has a great feature for this. Go to http://www.1010tires.com/, and click on the custom car wizard. That will let you see how different tires will look on your car without modifications.
Turn your wheels to the left,or right, to shortest distance tire is from front fenders, front, top, and backside. Measure distances for each, deduct about 1/2" to have enough clearance, that could change and cause tire to hit the finder when going down bumpy roads. Otherwise, more money for a lift kt, and flare fender would be required to be installed. In order to provide more clearance to support your desired size increase.
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