The wheel size is determined by the tire used. So if U want large wheels, U would have to use tires from a car with large rims like the Z concept, and install them with a gameshark code, or MK's.
First off THANX Heydu you've added a new dimension to my GT3 enjoyment!!!
One quick question: Is there any sort of chart available concerning tyre diameter??? Specifically am having problems w/Stratos & a few others showing the front tyres through the tops of the fenders & "trial & error" is a little tedious. Thanx again for all the great info...UB57
That problemcan generally be corrected with a ride height adjustment. i know i had a Stratos rally with it's own tires that didn't show thru, but the ride height was very high.
Otherwise, try downloading this Tire size chart , it may help.