Was curious how large a rim an '08 MCS can wear. I know this also counts on how low a profile of tire is worn on them. For a low profile tire that's not so low you get beat to death, how big a rim will fit under there and still allow reasonable shock deflection without body damage. 18's ?
I have factory 17's on Big Papi 205/45/R17 with runflats. I know someone has the same with a 205/40/R17. An 18 could possibly fit but as you said it would depend on the tire. Go to a wheel & tire place and have them mount one to see....